WorldWideScience

Sample records for surface area determination

  1. Determining Surface Roughness in Urban Areas Using Lidar Data

    Science.gov (United States)

    Holland, Donald

    2009-01-01

    An automated procedure has been developed to derive relevant factors, which can increase the ability to produce objective, repeatable methods for determining aerodynamic surface roughness. Aerodynamic surface roughness is used for many applications, like atmospheric dispersive models and wind-damage models. For this technique, existing lidar data was used that was originally collected for terrain analysis, and demonstrated that surface roughness values can be automatically derived, and then subsequently utilized in disaster-management and homeland security models. The developed lidar-processing algorithm effectively distinguishes buildings from trees and characterizes their size, density, orientation, and spacing (see figure); all of these variables are parameters that are required to calculate the estimated surface roughness for a specified area. By using this algorithm, aerodynamic surface roughness values in urban areas can then be extracted automatically. The user can also adjust the algorithm for local conditions and lidar characteristics, like summer/winter vegetation and dense/sparse lidar point spacing. Additionally, the user can also survey variations in surface roughness that occurs due to wind direction; for example, during a hurricane, when wind direction can change dramatically, this variable can be extremely significant. In its current state, the algorithm calculates an estimated surface roughness for a square kilometer area; techniques using the lidar data to calculate the surface roughness for a point, whereby only roughness elements that are upstream from the point of interest are used and the wind direction is a vital concern, are being investigated. This technological advancement will improve the reliability and accuracy of models that use and incorporate surface roughness.

  2. Experiment Study on Determination of Surface Area of Finegrained Soils by Mercury Intrusion Porosimetry

    Science.gov (United States)

    Yan, X. Q.; Zhou, C. Y.; Fang, Y. G.; Lin, L. S.

    2017-12-01

    The specific surface area (SSA) has a great influence on the physical and chemical properties of fine-grained soils. Determination of specific surface area is an important content for fine-grained soils micro-meso analysis and characteristic research. In this paper, mercury intrusion porosimetry (MIP) was adopted to determine the SSA of fine-grained soils including quartz, kaolinite, bentonite and natural Shenzhen soft clay. The test results show that the average values of SSA obtained by MIP are 0.78m2/g, 11.31m2/g, 57.28m2/g and 27.15m2/g respectively for very fine-grained quartz, kaolin, bentonite and natural Shenzhen soft clay, and that it is feasible to apply MIP to obtain the SSA of fine-grained soils through statistical analysis of 97 samples. Through discussion, it is necessary to consider the state of fine-grained soils such as pore ratio when the SSA of fine-grained soils is determined by MIP.

  3. Water surface area and depth determine oviposition choice in Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Reiskind, Michael H; Zarrabi, Ali A

    2012-01-01

    Oviposition choice is a well-studied aspect of the mosquito life cycle, and offers a potential avenue for species-specific surveillance and control. In container inhabiting mosquitoes, there has been a focus on how the components of the aquatic media determine choice, with little work on the physical characteristics of the containers themselves. We performed five experiments examining the effect of physical container parameters on oviposition choice by Aedes albopictus. We examined containers of three different surface areas (small, 496 cm2; medium, 863 cm2; and large, 1,938 cm2) at the same water depth and the same or different heights in a series of binary choice assays. We also examined different depths with the same surface area in clear containers (where the depth may be perceived by the darkness of the water) and in opaque containers, which appear uniformly dark at different depths. We found a significant preference for medium containers over large containers, whether the containers were different or the same heights, and a trend toward a preference for small containers over medium containers. There was a preference for deeper water regardless of whether containers were clear or opaque. These behaviors suggest mosquitoes take into account physical aspects of their habitats and their oviposition choices are consistent with minimizing the risk of habitat drying.

  4. Idealized Shale Sorption Isotherm Measurements to Determine Pore Volume, Pore Size Distribution, and Surface Area

    Science.gov (United States)

    Holmes, R.; Wang, B.; Aljama, H.; Rupp, E.; Wilcox, J.

    2014-12-01

    One method for mitigating the impacts of anthropogenic CO2-related climate change is the sequestration of CO2 in depleted gas and oil reservoirs, including shale. The accurate characterization of the heterogeneous material properties of shale, including pore volume, surface area, pore size distributions (PSDs) and composition is needed to understand the interaction of CO2 with shale. Idealized powdered shale sorption isotherms were created by varying incremental amounts of four essential components by weight. The first two components, organic carbon and clay, have been shown to be the most important components for CO2 uptake in shales. Organic carbon was represented by kerogen isolated from a Silurian shale, and clay groups were represented by illite from the Green River shale formation. The rest of the idealized shale was composed of equal parts by weight of SiO2 to represent quartz and CaCO3 to represent carbonate components. Baltic, Eagle Ford, and Barnett shale sorption measurements were used to validate the idealized samples. The idealized and validation shale sorption isotherms were measured volumetrically using low pressure N2 (77K) and CO2 (273K) adsorbates on a Quantachrome Autosorb IQ2. Gravimetric isotherms were also produced for a subset of these samples using CO2 and CH4adsorbates under subsurface temperature and pressure conditions using a Rubotherm magnetic suspension balance. Preliminary analyses were inconclusive in validating the idealized samples. This could be a result of conflicting reports of total organic carbon (TOC) content in each sample, a problem stemming from the heterogeneity of the samples and different techniques used for measuring TOC content. The TOC content of the validation samples (Eagle Ford and Barnett) was measured by Rock-Eval pyrolysis at Weatherford Laboratories, while the TOC content in the Baltic validation samples was determined by LECO TOC. Development of a uniform process for measuring TOC in the validation samples is

  5. Determination of the surface area and sizes of supported copper nanoparticles through organothiol adsorption—ñhemisorption

    International Nuclear Information System (INIS)

    Ndolomingo, Matumuene Joe; Meijboom, Reinout

    2016-01-01

    Highlights: • Cu on γ-Al 2 O 3 catalysts were prepared and characterized. • The ligand sorption-based technique was used for the determination of specific surface area and particle sizes. • The ligand packing density on Cu nanoparticles was quantified. • A fair agreement was found between the Cu particle sizes obtained from ligand adsorption and TEM methods. • The oxidation of morin by hydrogen peroxide was used to evaluate the catalytic activities of the Cu supported catalysts. - Abstract: The mechanisms involving the nanoparticle surfaces in catalytic reactions are more difficult to elucidate due to the nanoparticle surface unevenness, size distributions, and morphological irregularity. True surface area and particle sizes determination are key aspects of the activity of metal nanoparticle catalysts. Here we report on the organothiol adsorption-based technique for the determination of specific surface area of Cu nanoparticles, and their resultant sizes on γ-Al 2 O 3 supports. Quantification of ligand packing density on copper nanoparticles is also reported. The concentration of the probe ligand, 2-mercaptobenzimidazole (2-MBI) before and after immersion of supported copper catalysts was determined by ultraviolet-visible spectrometry (UV–vis). The amount of ligand adsorbed was found to be proportional to the copper nanoparticles surface area. Atomic absorption spectrometry (AAS), N 2 -physisorption (BET), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) were used for the characterization of the catalysts. A fair agreement was found between particle sizes obtained from ligand adsorption and TEM methods. The catalytic activity of the copper nanoparticles related to their inherent surface area was evaluated using the model reaction of the oxidation of morin by hydrogen peroxide.

  6. Determination of the surface area and sizes of supported copper nanoparticles through organothiol adsorption—ñhemisorption

    Energy Technology Data Exchange (ETDEWEB)

    Ndolomingo, Matumuene Joe; Meijboom, Reinout, E-mail: rmeijboom@uj.ac.za

    2016-12-30

    Highlights: • Cu on γ-Al{sub 2}O{sub 3} catalysts were prepared and characterized. • The ligand sorption-based technique was used for the determination of specific surface area and particle sizes. • The ligand packing density on Cu nanoparticles was quantified. • A fair agreement was found between the Cu particle sizes obtained from ligand adsorption and TEM methods. • The oxidation of morin by hydrogen peroxide was used to evaluate the catalytic activities of the Cu supported catalysts. - Abstract: The mechanisms involving the nanoparticle surfaces in catalytic reactions are more difficult to elucidate due to the nanoparticle surface unevenness, size distributions, and morphological irregularity. True surface area and particle sizes determination are key aspects of the activity of metal nanoparticle catalysts. Here we report on the organothiol adsorption-based technique for the determination of specific surface area of Cu nanoparticles, and their resultant sizes on γ-Al{sub 2}O{sub 3} supports. Quantification of ligand packing density on copper nanoparticles is also reported. The concentration of the probe ligand, 2-mercaptobenzimidazole (2-MBI) before and after immersion of supported copper catalysts was determined by ultraviolet-visible spectrometry (UV–vis). The amount of ligand adsorbed was found to be proportional to the copper nanoparticles surface area. Atomic absorption spectrometry (AAS), N{sub 2}-physisorption (BET), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) were used for the characterization of the catalysts. A fair agreement was found between particle sizes obtained from ligand adsorption and TEM methods. The catalytic activity of the copper nanoparticles related to their inherent surface area was evaluated using the model reaction of the oxidation of morin by hydrogen peroxide.

  7. Calorimetry by immersion into liquid nitrogen and liquid argon: a better way to determine the internal surface area of micropores.

    Science.gov (United States)

    Navarrete, Ricardo; Llewellyn, Philip; Rouquerol, Françoise; Denoyel, Renaud; Rouquerol, Jean

    2004-09-15

    The aim of this work is to assess the internal surface area of a set of samples (either carbons or oxides, either porous or nonporous, either microporous or mesoporous) by microcalorimetry via immersion into liquid nitrogen or argon. We have made use of an isothermal, heat-flux microcalorimeter, initially designed and built in our laboratory for the sake of gas adsorption experiments at 77 or 87 K. It seems that immersion calorimetry into liquid nitrogen and argon makes it possible to go one step further in the determination of the internal surface area of micropores.

  8. Use of cyclic voltammetry and electrochemical impedance spectroscopy for determination of active surface area of modified carbon-based electrodes

    International Nuclear Information System (INIS)

    Souza, Leticia Lopes de

    2011-01-01

    Carbon-based electrodes as well the ion exchange electrodes among others have been applied mainly in the treatment of industrial effluents and radioactive wastes. Carbon is also used in fuel cells as substrate for the electrocatalysts, having high surface area which surpasses its geometric area. The knowledge of the total active area is important for the determination of operating conditions of an electrochemical cell with respect to the currents to be applied (current density). In this study it was used two techniques to determine the electrochemical active surface area of glassy carbon, electrodes and ion exchange electrodes: cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The experiments were carried out with KNO 3 0.1 mol.L -1 solutions in a three-electrode electrochemical cell: carbon-based working electrode, platinum auxiliary electrode and Ag/AgCl reference electrode. The glassy carbon and porous carbon electrodes with geometric areas of 3.14 x 10 -2 and 2.83 X 10 -1 cm 2 , respectively, were used. The ion exchange electrode was prepared by mixing graphite, carbon, ion exchange resin and a binder, and this mixture was applied in three layers on carbon felt, using a geometric area of 1.0 cm 2 during the experiments. The capacitance (Cd) of the materials was determined by EIS using Bode diagrams. The value of 172 μF.cm -2 found for the glassy carbon is consistent with the literature data (∼ 200 μF.cm'- 2 ). By VC, varying the scan rate from 0.2 to 2.0 mV.s-1, the capacitance CdS (S = active surface area) in the region of the electric double layer (EDL) of each material was determined. By EIS, the values of C d , 3.0 x 10 -5 μF.cm'- 2 and 11 x 10 3 μF.cm-2, were found for the porous carbon and ion exchange electrodes, respectively, which allowed the determination of active surface areas as 3.73 x 106 cm 2 and 4.72 cm 2 . To sum up, the combined use of EIS and CV techniques is a valuable tool for the calculation of active surface

  9. Determination of BTEX in surface and ground waters at Centro Experimental Aramar area

    International Nuclear Information System (INIS)

    Matoso, Erika; Oliveira, Rando M. de; Segre, Nádia

    2017-01-01

    The mixture of the monocyclic aromatic compounds benzene, toluene, ethylbenzene and xylene isomers is defined as BTEX. The presence of BTEX in the environment is regularly associated with petroleum and its byproducts leakages or industrial effluent discharge. BTEX may cause serious problems to human and animal health. Human exposure to these aromatic compounds can lead to eye and skin irritation, central nervous system weakening and bone marrow depression. According to World Health Organization (WHO) benzene can cause cancer development. A new unit process in Centro Experimental Aramar (CEA) using BTEX-containing products will be launched shortly. Therefore, BTEX monitoring will be necessary since effluents release in Brazil is controlled by CONAMA regulations. Besides, as these compounds has never been evaluated in CEA, it is important to provide knowledge on the current BTEX concentration, in order to establish pre-operational values in CEA region and nearby. The CONAMA regulations for BTEX in superficial waters sets very low limits (such as 0,002 mg L- 1 for toluene and 0,005 mg L-1 for benzene). For this reason, it was developed in this work an analytical method by Headspace-GC-MS to achieve these values. The figures of merit determined were limit of detection (LOD), limit of quantification (LOQ), precision and accuracy. BTEX was analyzed in superficial waters from three different sampling points at Ipanema River and ground water collected in eight different sampling points. All sampling points were located a ratio 10 km radius from CEA. (author)

  10. Determination of BTEX in surface and ground waters at Centro Experimental Aramar area

    Energy Technology Data Exchange (ETDEWEB)

    Matoso, Erika; Oliveira, Rando M. de; Segre, Nádia, E-mail: ematoso@hotmail.com [Centro Tecnológico da Marinha em São Paulo (CEA/CTMSP), Iperó, SP (Brazil). Centro Experimental Aramar

    2017-07-01

    The mixture of the monocyclic aromatic compounds benzene, toluene, ethylbenzene and xylene isomers is defined as BTEX. The presence of BTEX in the environment is regularly associated with petroleum and its byproducts leakages or industrial effluent discharge. BTEX may cause serious problems to human and animal health. Human exposure to these aromatic compounds can lead to eye and skin irritation, central nervous system weakening and bone marrow depression. According to World Health Organization (WHO) benzene can cause cancer development. A new unit process in Centro Experimental Aramar (CEA) using BTEX-containing products will be launched shortly. Therefore, BTEX monitoring will be necessary since effluents release in Brazil is controlled by CONAMA regulations. Besides, as these compounds has never been evaluated in CEA, it is important to provide knowledge on the current BTEX concentration, in order to establish pre-operational values in CEA region and nearby. The CONAMA regulations for BTEX in superficial waters sets very low limits (such as 0,002 mg L- 1 for toluene and 0,005 mg L-1 for benzene). For this reason, it was developed in this work an analytical method by Headspace-GC-MS to achieve these values. The figures of merit determined were limit of detection (LOD), limit of quantification (LOQ), precision and accuracy. BTEX was analyzed in superficial waters from three different sampling points at Ipanema River and ground water collected in eight different sampling points. All sampling points were located a ratio 10 km radius from CEA. (author)

  11. High surface area calcite

    Science.gov (United States)

    Schultz, L. N.; Andersson, M. P.; Dalby, K. N.; Müter, D.; Okhrimenko, D. V.; Fordsmand, H.; Stipp, S. L. S.

    2013-05-01

    Calcite (CaCO3) is important in many fields—in nature, because it is a component of aquifers, oil reservoirs and prospective CO2 storage sites, and in industry, where it is used in products as diverse as paper, toothpaste, paint, plastic and aspirin. It is difficult to obtain high purity calcite with a high surface area but such material is necessary for industrial applications and for fundamental calcite research. Commercial powder is nearly always contaminated with growth inhibitors such as sugars, citrate or pectin and most laboratory synthesis methods deliver large precipitates, often containing vaterite or aragonite. To address this problem, we (i) adapted the method of carbonating a Ca(OH)2 slurry with CO2 gas to develop the first simple, cheap, safe and reproducible procedure using common laboratory equipment, to obtain calcite that reproducibly had a surface area of 14-17 m2/g and (ii) conducted a thorough characterization of the product. Scanning electron microscopy (SEM) revealed nanometer scale, rhombohedral crystals. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) confirmed highly crystalline, pure calcite that more closely resembles the dimensions of the biogenic calcite produced by algae in coccoliths than other methods for synthesizing calcite. We suggest that this calcite is useful when purity and high surface area are important.

  12. Determination of the adsorbent specific surface area at tar removing from industrial waste water of ammonium sulphate production

    Directory of Open Access Journals (Sweden)

    A.V. Ivanchenko

    2016-12-01

    Full Text Available At most coke plants of Ukraine and the world, ammonium sulphate (NH42SO4, which is an ammonium fertilizer, get in the department of trapping chemical products of coking. The liquid wastes formed in this department called phenolic wastewater, the main polluting agents of which are tarry substances. When choosing industrial adsorbent for wastewater treatment, the value of specific surface area is a determining factor. The high cost of modern industrial sorbents causes necessity of finding of new, more affordable their analogs, among which of particular interest are natural bentonite clays. Aim: The aim of research is to study the regularities of extraction process of tarry substances of manufacturing sewage of a ammonium sulphate with use of sodium and calcium bentonites, an absorbite and peat, and definition of a specific surface area of the specified adsorbents. Materials and Methods: In this study the absorbite AG-5, valley peat and natural sodium and calcium bentonite clays are used as sorbents. The adsorption of tar substances had been researched during the flotation process of phenolic wastewater in conditions close to industrial: the duration of flotation is 20 min; the wastewater temperature is 323 K; the intensity of air supply – 0.15 dm3/h. The calculations suggested that the adsorption of tarry substances is monomolecular in nature and described by the Langmuir’s theory of monomolecular adsorption. Results: The specific surface area of the adsorbents during the adsorption process of tarry substances from a phenolic industrial wastewater defined for the first time are following (m2/g: sodium bentonite clay – 1847; absorbite AG-5 – 1467; calcium bentonite clay – 728; valley peat – 603. For these adsorbents was also calculated the limit value of adsorption and constant of adsorption equilibria. The obtained values indicate a strong interaction between adsorbent and adsorbate, especially significant for the bentonite clay and

  13. Determination of surface and groundwater quality in the Orontes basin (Syria) and the negative effect of some pollutants on the water, soil, and plants at this area

    International Nuclear Information System (INIS)

    Kassem, A.

    2005-01-01

    This work deals with the physical/chemical characteristics and quality of surface and ground water in the basin of the Orontes river in Syria. It also deals with concentration of basic elements and trace elements in water, soil and some plant leaves in that area. The internationally acknowledged methods were used to determine the physical constituents and to analyze elements of the most important basic and sub compounds in 95 water samples (77 ground samples and 18 surface samples). The instrumental Neutron Activation Analysis was used to analyze some major elements and trace elements in 18 soil samples and 9 plant leave samples. Evaluation of analysis results of those samples shows the great geo-ecological and geographic effect and the effect of human activities on polluting the water, soil and plants according to quality of irrigation water, effect of air, liquid and solid rejects of the industrial and municipal sites, nature and repetition of plantations and type of fertilizers and pesticides used in the studied area.(author)

  14. Heavy metals, salts and organic residues in old solid urban waste landfills and surface waters in their discharge areas: determinants for restoring their impact.

    Science.gov (United States)

    Pastor, J; Hernández, A J

    2012-03-01

    This study was designed to determine the state of polluted soils in the main landfills of the Community of Madrid (central Spain), as part of a continuous assessment of the impacts of urban solid waste (USW) landfills that were capped with a layer of soil 20 years ago. Our analysis of this problem has been highly conditioned by the constant re-use of many of the USW landfills, since they have never been the target of any specific restoration plan. Our periodical analysis of cover soils and soils from discharge areas of the landfills indicates soil pollution has worsened over the years. Here, we examined heavy metal, salts, and organic compounds in soil and surface water samples taken from 15 landfills in the Madrid region. Impacts of the landfill soil covers on nematode and plant diversity were also evaluated. These analyses continue to reveal the presence of heavy metals (Zn, Cu, Cr, Ni, Pb, Cd) in soils, and salts (sulphates, chlorides and nitrates) in soils and surface waters. In addition, non-agricultural organic compounds, mainly aromatic and aliphatic hydrocarbons, often appeared in very high concentrations, and high levels of insecticides such as gamma-HCH (lindane) were also detected in soils. Around 50% of the water samples collected showed chemical demand of oxygen (CDO) values in excess of 150 mg/l. Traces of phenolic compounds were detected in some landfills, some of which exhibited high levels of 2-chlorophenol and pentachlorophenol. All these factors are conditioning both the revegetation of the landfill systems and the remediation of their slopes and terrestrial ecosystems arising in their discharge areas. This work updates the current situation and discusses risks for the health of the ecosystems, humans, domestic animals and wildlife living close to these landfills. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Determination of particle concentration rankings by spatial mapping of particle surface area, number, and mass concentrations in a restaurant and a die casting plant.

    Science.gov (United States)

    Park, Ji Young; Ramachandran, Gurumurthy; Raynor, Peter C; Olson, Gregory M

    2010-08-01

    Measurements using several exposure metrics were carried out in a restaurant and a die casting plant to compare the spatial distributions of particle surface area (SA), number, and mass concentrations and rank exposures in different areas by those metrics. The different exposure metrics for incidental nanoparticle and fine particle exposures were compared using the concentration rankings, statistical differences between areas, and concentration ratios between different areas. In the die casting plant, area concentration rankings and spatial distributions differed by the exposure metrics chosen. Surface area and fine particle number concentrations were greatest near incidental nanoparticle sources and were significantly different between three areas. However, mass and coarse particle number concentrations were similar throughout the facility, and rankings of the work areas based on these metrics were different from those of SA and fine number concentrations. In the restaurant, concentrations in the kitchen for all metrics except respirable mass concentration were significantly greater than in the serving area, although SA and fine particle number concentrations showed larger differences between the two areas than either the mass or coarse particle number concentrations. Thus, the choice of appropriate exposure metric has significant implications for exposure groupings in epidemiologic and occupational exposure studies.

  16. Analysis of changes in hardness of a metal surface layer in areas of high stress and methods of determining residual life of parts for mining machines

    Science.gov (United States)

    Zvonarev, I. E.; Ivanov, S. L.

    2016-02-01

    The methodological bases for determining the energy resource of mechanical transmissions details for mining machines are considered. Based on the analysis of the accumulation of damage in metal gears, a method of estimating residual life of coarse-toothed wheels by periodically measuring the hardness of the surface layer of the teeth is justified. The regularities in change of hardness of coarse-tooth gear, conditioned by a change in metal strength properties that take into account the micro- and macromechanisms of plastic and elastic deformation, distortion of the metal crystal lattice with formation and movement of vacancies and dislocations. Experimental setup was built and the results of laboratory experiments are given related to the process of destruction of non-standard samples under different loads. Comparison of dimensions and hardness values of the sample allows concluding that a larger deformation corresponds to a greater increase in hardness, their limit value for the material being in the fracture zone. It is established that the detected changes in the local hardness occurs in areas of increased stresses above the limit of proportionality and the work of fracture forces attributed to dislocations density adjacent to the fracture plane expressed in terms of hardness increment is constant.

  17. Surface texturing of crystalline silicon and effective area measurement

    Science.gov (United States)

    Sun, Tietun; Chen, Dong; Chui, Rongqiang

    2000-11-01

    In this paper, the surface area of solar cell is determined by the capacitance measurements of MOS structure. The texture etching technology can be controlled according to the change of silicon surface area, furthermore, the textured silicon surface and interface characteristic of solar cell can be studied by measuring the relationship of capacitance and voltage for MOS structure.

  18. Heavy metals, salts and organic residues in solid urban waste landfills and surface waters in their discharge areas: determinants for restoring their discharge areas: determinants for restoring their impact

    International Nuclear Information System (INIS)

    Hernandez, A. J.; Pastor, J.

    2009-01-01

    This report describes a continuous assessment of the impact of solid urban waste (SUW) landfills in the central Iberian Peninsula that were sealed with a layer of soil 20 years ago. cover soils and soils from discharge areas have been periodically analysed. Soil concentrations of salts and heavy metals affect the biotic components of these ecosystems. (Author)

  19. Determination of free cyanide and total cyanide concentrations in surface and underground waters in Bogoso and its surrounding areas in Ghana

    Directory of Open Access Journals (Sweden)

    S. Obiri

    2007-08-01

    Full Text Available Concentrations of free cyanide and total cyanide in water samples in Bogoso and its surrounding areas in Ghana have been measured in this study. Concentrations of free cyanide and total cyanide were found to be above the maximum permissible discharge limit of effluent from mining companies into natural waters set by Environmental Protection Agency, Ghana (GEPA. A comparison of the results obtained in this study with permissible levels set by US Environmental Protection Agency and the World Health Organization reveals that surface waters in the study areas are highly polluted with cyanide and it's not safe for human consumptions. This means that, the resident in and around Bogoso are at risk.

  20. Contact area measurements on structured surfaces

    DEFF Research Database (Denmark)

    Kücükyildiz, Ömer Can; Jensen, Sebastian Hoppe Nesgaard; De Chiffre, Leonardo

    In connection with the use of brass specimens featuring structured surfaces in a tribology test, an algorithm was developed for automatic measurement of the contact area by optical means.......In connection with the use of brass specimens featuring structured surfaces in a tribology test, an algorithm was developed for automatic measurement of the contact area by optical means....

  1. Surface moisture estimation in urban areas

    Science.gov (United States)

    Jiang, Yitong

    Surface moisture is an important parameter because it modifies urban microclimate and surface layer meteorology. The primary objectives of this paper are: 1) to analyze the impact of surface roughness from buildings on surface moisture in urban areas; and 2) to quantify the impact of surface roughness resulting from urban trees on surface moisture. To achieve the objectives, two hypotheses were tested: 1) the distribution of surface moisture is associated with the structural complexity of buildings in urban areas; and 2) The distribution and change of surface moisture is associated with the distribution and vigor of urban trees. The study area is Indianapolis, Indiana, USA. In the part of the morphology of urban trees, Warren Township was selected due to the limitation of tree inventory data. To test the hypotheses, the research design was made to extract the aerodynamic parameters, such as frontal areas, roughness length and displacement height of buildings and trees from Terrestrial and Airborne LiDAR data, then to input the aerodynamic parameters into the urban surface energy balance model. The methodology was developed for comparing the impact of aerodynamic parameters from LiDAR data with the parameters that were derived empirically from land use and land cover data. The analytical procedures are discussed below: 1) to capture the spatial and temporal variation of surface moisture, daily and hourly Land Surface Temperature (LST) were downscaled from 4 km to 1 km, and 960 m to 30 m, respectively, by regression between LST and various components that impact LST; 2) to estimate surface moisture, namely soil moisture and evapotranspiration (ET), land surfaces were classified into soil, vegetation, and impervious surfaces, using Linear Spectral Mixture Analysis (LSMA); 3) aerodynamic parameters of buildings and trees were extracted from Airborne and Terrestrial LiDAR data; 4) the Temperature-Vegetation-Index (TVX) method, and the Two-Source-Energy-Balance (TSEB

  2. Determination of area averaged water vapour fluxes with large aperture and radio wave scintillometers over a heterogeneous surface - Flevoland field experiment

    NARCIS (Netherlands)

    Meijninger, W.M.L.; Green, A.E.; Hartogensis, O.K.; Kohsiek, W.; Hoedjes, J.C.B.; Zuurbier, R.M.; DeBruin, H.A.R.

    2002-01-01

    A large aperture scintillometer (LAS) and radio wave scintillometer (RWS) were installed over a heterogeneous area to test the applicability of the scintillation method. The heterogeneity in the area, which consisted of many plots, was mainly caused by differences in thermal properties of the crops;

  3. Monitoring System for ALICE Surface Areas

    CERN Document Server

    Demirbasci, Oguz

    2016-01-01

    I have been at CERN for 12 weeks within the scope of Summer Student Programme working on a monitoring system project for surface areas of the ALICE experiment during this period of time. The development and implementation of a monitoring system for environmental parameters in the accessible areas where a cheap hardware setup can be deployed were aim of this project. This report explains how it was developed by using Arduino, Raspberry PI, WinCC OA and DIM protocol.

  4. Volumes and surface areas of pendular rings

    Science.gov (United States)

    Rose, W.

    1958-01-01

    A packing of spheres is taken as a suitable model of porous media. The packing may be regular and the sphere size may be uniform, but in general, both should be random. Approximations are developed to give the volumes and surface areas of pendular rings that exist at points of sphere contact. From these, the total free volume and interfacial specific surface area are derived as expressive of the textural character of the packing. It was found that the log-log plot of volumes and surface areas of pendular rings vary linearly with the angle made by the line joining the sphere centers and the line from the center of the largest sphere to the closest edge of the pendular ring. The relationship, moreover, was found not to be very sensitive to variation in the size ratio of the spheres in contact. It also was found that the addition of pendular ring material to various sphere packings results in an unexpected decrease in the surface area of the boundaries that confine the resulting pore space. ?? 1958 The American Institute of Physics.

  5. Estimating surface area in early hominins.

    Directory of Open Access Journals (Sweden)

    Alan Cross

    Full Text Available Height and weight-based methods of estimating surface area have played an important role in the development of the current consensus regarding the role of thermoregulation in human evolution. However, such methods may not be reliable when applied to early hominins because their limb proportions differ markedly from those of humans. Here, we report a study in which this possibility was evaluated by comparing surface area estimates generated with the best-known height and weight-based method to estimates generated with a method that is sensitive to proportional differences. We found that the two methods yield indistinguishable estimates when applied to taxa whose limb proportions are similar to those of humans, but significantly different results when applied to taxa whose proportions differ from those of humans. We also found that the discrepancy between the estimates generated by the two methods is almost entirely attributable to inter-taxa differences in limb proportions. One corollary of these findings is that we need to reassess hypotheses about the role of thermoregulation in human evolution that have been developed with the aid of height and weight-based methods of estimating body surface area. Another is that we need to use other methods in future work on fossil hominin body surface areas.

  6. Osmosis and Surface Area to Volume Ratio.

    Science.gov (United States)

    Barrett, D. R. B.

    1984-01-01

    Describes an experiment designed to help students understand the concepts of osmosis and surface area to volume ratio (SA:VOL). The task for students is to compare water uptake in different sizes of potato cubes and relate differences to their SA:VOL ratios. (JN)

  7. On semiautomatic estimation of surface area

    DEFF Research Database (Denmark)

    Dvorak, J.; Jensen, Eva B. Vedel

    2013-01-01

    . For convex particles, the estimator is equal to four times the area of the support set (flower set) of the particle transect. We study the statistical properties of the flower estimator and compare its performance to that of two discretizations of the flower estimator, namely the pivotal estimator......In this paper, we propose a semiautomatic procedure for estimation of particle surface area. It uses automatic segmentation of the boundaries of the particle sections and applies different estimators depending on whether the segmentation was judged by a supervising expert to be satisfactory....... If the segmentation is correct the estimate is computed automatically, otherwise the expert performs the necessary measurements manually. In case of convex particles we suggest to base the semiautomatic estimation on the so-called flower estimator, a new local stereological estimator of particle surface area...

  8. Characterization of high surface area silicon oxynitrides

    International Nuclear Information System (INIS)

    Lednor, P.W.; DeRuiter, R.; Emeis, K.A.

    1992-01-01

    In heterogenous catalysis, liquid or gaseous feedstocks are converted over a solid catalyst into more desirable products. Such processes form an essential part of the oil and petrochemical industries. The solid catalyst usually consists of an inorganic phase, with or without metal particles on the surface. Examples include platinum particles on gamma alumina (a reforming catalyst used in oil processing), chromium particles on silica (an ethylene polymerization catalyst) and zeolites or amorphous silica-aluminas (used as solid acids).Oxides have been widely investigated in catalysis, and silica, alumina, and aluminosilicates find application commercially on a large scale. On the other hand, non-oxide materials such as nitrides, carbides and borides have been relatively little investigated. The main reason for this has been the lack of routes to the high surface area forms usually required in catalysis. However, this situation has changed significantly in recent years, due to the interest in high surface area non-oxides as precursors to fully dense ceramics; in this paper, the authors have reviewed synthetic routes to high surface area non-oxides

  9. Hand surface area as a percentage of body surface area in Asian children: a pilot study.

    Science.gov (United States)

    Choi, Hyuk; Park, Man Sik; Lee, Heung-Man

    2011-09-01

    The hand surface area (HSA) of one hand has been estimated as 1% of the body surface area (BSA). This does change with the patient's age, gender, and body mass index (BMI). There are many HSA studies done on adult populations, but fewer done on children. Our hypothesis in this study is that the general HSA equation for Caucasian adults cannot be applied as accurately to children and Asian people. HSA was defined as the area of the palm without fingers in this study. Children are in a stage of growth. If a child's hand growth ratio is not the same as that of an adult, the result of HSA/BSA calculation could be different. We undertook this study to determine whether or not there were any differences in HSA/BSA among Korean children (7-18 years) and adults (20-60 years), and compared our results with western data. A total of 186 boys aged between 7 and 18 years, were recruited for this study; their HSA was measured, directly. A total of 186 adults aged between 20 and 60 years were selected as well. BSA was calculated only for volunteers in subjects who HSA had been measured. From these results, HSA/BSA was calculated. HSA/BSA ratio of Korean boys was 0.69±0.05%, which was less than 1%. It is suggested that the ratio of the western data may not be applicable to Asian children, particularly, Korean children. HSA/BSA ratio can be applied in administration of drug doses and estimation of the area of burns. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  10. Determination of the effective thickness of a porous electrode in a flow-through reactor: effect of the specific surface area of stainless steel fibres, used as a porous cathode, during the deposition of Ag(I) ions

    OpenAIRE

    Nava Montes de Oca, José Luis; Oropeza Guzmán, Mercedes T.; Ponce de León Albarrán, Carlos; González García, José; Frías Ferrer, Ángel

    2007-01-01

    This study discusses the use of potential distribution analysis during the deposition of metal ions, at limiting current conditions and determines the optimum electrode thickness at which no hydrogen evolution occurs. The potential distribution studies were carried out on stainless-steel fibres of three different surface areas. The fibres were used as cathodic porous electrodes during the deposition of Ag(I) ions contained in 0.1 mol dm? 3 KNO3 and 0.6 mol dm? 3 NH4OH electrolyte. The compari...

  11. High Surface Area Tunnels in Hexagonal WO₃.

    Science.gov (United States)

    Sun, Wanmei; Yeung, Michael T; Lech, Andrew T; Lin, Cheng-Wei; Lee, Chain; Li, Tianqi; Duan, Xiangfeng; Zhou, Jun; Kaner, Richard B

    2015-07-08

    High surface area in h-WO3 has been verified from the intracrystalline tunnels. This bottom-up approach differs from conventional templating-type methods. The 3.67 Å diameter tunnels are characterized by low-pressure CO2 adsorption isotherms with nonlocal density functional theory fitting, transmission electron microscopy, and thermal gravimetric analysis. These open and rigid tunnels absorb H(+) and Li(+), but not Na(+) in aqueous electrolytes without inducing a phase transformation, accessing both internal and external active sites. Moreover, these tunnel structures demonstrate high specific pseudocapacitance and good stability in an H2SO4 aqueous electrolyte. Thus, the high surface area created from 3.67 Å diameter tunnels in h-WO3 shows potential applications in electrochemical energy storage, selective ion transfer, and selective gas adsorption.

  12. Estimation of surface area and surface area measure of three-dimensional sets from digitizations

    DEFF Research Database (Denmark)

    Ziegel, Johanna; Kiderlen, Markus

    2010-01-01

    A local method for estimating surface area and surface area measure of three-dimensional objects from discrete binary images is presented. A weight is assigned to each 2 × 2 × 2 configuration of voxels and the total surface area of an object is given by summation of the local area contributions....... The method is based on an exact asymptotic result that holds for increasing resolution of the digitization. It states that the number of occurrences of a 2 ×  2 × 2 configuration is asymptotically proportional to an integral of its “h-function” with respect to the surface area measure of the object. We find...

  13. In-situ determination of trace metal species in surface waters of Black Sea coastal area: comparison to bioavailability by green microalgae

    OpenAIRE

    Slaveykova, Vera; Karadjova, Irina B; Karadjov, Metody; Tsalev, Dimiter L

    2009-01-01

    Trace metal speciation in seawater from the Bulgarian Black Sea coast was studied in situ by hollow fiber permeation liquid membrane (HF-PLM) and by diffusion gradients in thin- film gels (DGT). The concentrations of Cd, Cu, Ni, and Pb determined by HF-PLM were lower than those measured by DGT, in agreement with their analytical windows, e.g., free metal ions provided by the HF-PLM and dynamic (mobile and labile) species by the DGT. The obtained suite of data was further used to evalua...

  14. High surface area fibrous silica nanoparticles

    KAUST Repository

    Polshettiwar, Vivek

    2014-11-11

    Disclosed are high surface area nanoparticles that have a fibrous morphology. The nanoparticles have a plurality of fibers, wherein each fiber is in contact with one other fiber and each fiber has a length of between about 1 nm and about 5000 nm. Also disclosed are applications of the nanoparticles of the present invention, and methods of fabrication of the nanoparticles of the present invention.

  15. Can foot anthropometric measurements predict dynamic plantar surface contact area?

    Directory of Open Access Journals (Sweden)

    Collins Natalie

    2009-10-01

    Full Text Available Abstract Background Previous studies have suggested that increased plantar surface area, associated with pes planus, is a risk factor for the development of lower extremity overuse injuries. The intent of this study was to determine if a single or combination of foot anthropometric measures could be used to predict plantar surface area. Methods Six foot measurements were collected on 155 subjects (97 females, 58 males, mean age 24.5 ± 3.5 years. The measurements as well as one ratio were entered into a stepwise regression analysis to determine the optimal set of measurements associated with total plantar contact area either including or excluding the toe region. The predicted values were used to calculate plantar surface area and were compared to the actual values obtained dynamically using a pressure sensor platform. Results A three variable model was found to describe the relationship between the foot measures/ratio and total plantar contact area (R2 = 0.77, p R2 = 0.76, p Conclusion The results of this study indicate that the clinician can use a combination of simple, reliable, and time efficient foot anthropometric measurements to explain over 75% of the plantar surface contact area, either including or excluding the toe region.

  16. Particle surface area and bacterial activity in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Per Bovbjerg; von Ahnen, Mathis; Fernandes, Paulo

    2017-01-01

    Suspended particles in recirculating aquaculture systems (RAS) provide surface area that can be colonized by bacteria. More particles accumulate as the intensity of recirculation increases thus potentially increasing the bacterial carrying capacity of the systems. Applying a recent, rapid, cultur...... for determining bacterial activity might provide a means for future monitoring and assessment of microbial water quality in aquaculture farming systems......Suspended particles in recirculating aquaculture systems (RAS) provide surface area that can be colonized by bacteria. More particles accumulate as the intensity of recirculation increases thus potentially increasing the bacterial carrying capacity of the systems. Applying a recent, rapid, culture......-independent fluorometric detection method (Bactiquant®) for measuring bacterial activity, the current study explored the relationship between total particle surface area (TSA, derived from the size distribution of particles >5 μm) and bacterial activity in freshwater RAS operated at increasing intensity of recirculation...

  17. A Simple Proof of Cauchy's Surface Area Formula

    OpenAIRE

    Tsukerman, Emmanuel; Veomett, Ellen

    2016-01-01

    We give a short and simple proof of Cauchy's surface area formula, which states that the average area of a projection of a convex body is equal to its surface area up to a multiplicative constant in the dimension.

  18. Determination of leakage areas in nuclear piping

    International Nuclear Information System (INIS)

    Keim, E.

    1997-01-01

    For the design and operation of nuclear power plants the Leak-Before-Break (LBB) behavior of a piping component has to be shown. This means that the length of a crack resulting in a leak is smaller than the critical crack length and that the leak is safely detectable by a suitable monitoring system. The LBB-concept of Siemens/KWU is based on computer codes for the evaluation of critical crack lengths, crack openings, leakage areas and leakage rates, developed by Siemens/KWU. In the experience with the leak rate program is described while this paper deals with the computation of crack openings and leakage areas of longitudinal and circumferential cracks by means of fracture mechanics. The leakage areas are determined by the integration of the crack openings along the crack front, considering plasticity and geometrical effects. They are evaluated with respect to minimum values for the design of leak detection systems, and maximum values for controlling jet and reaction forces. By means of fracture mechanics LBB for subcritical cracks has to be shown and the calculation of leakage areas is the basis for quantitatively determining the discharge rate of leaking subcritical through-wall cracks. The analytical approach and its validation will be presented for two examples of complex structures. The first one is a pipe branch containing a circumferential crack and the second one is a pipe bend with a longitudinal crack

  19. Determination of leakage areas in nuclear piping

    Energy Technology Data Exchange (ETDEWEB)

    Keim, E. [Siemens/KWU, Erlangen (Germany)

    1997-04-01

    For the design and operation of nuclear power plants the Leak-Before-Break (LBB) behavior of a piping component has to be shown. This means that the length of a crack resulting in a leak is smaller than the critical crack length and that the leak is safely detectable by a suitable monitoring system. The LBB-concept of Siemens/KWU is based on computer codes for the evaluation of critical crack lengths, crack openings, leakage areas and leakage rates, developed by Siemens/KWU. In the experience with the leak rate program is described while this paper deals with the computation of crack openings and leakage areas of longitudinal and circumferential cracks by means of fracture mechanics. The leakage areas are determined by the integration of the crack openings along the crack front, considering plasticity and geometrical effects. They are evaluated with respect to minimum values for the design of leak detection systems, and maximum values for controlling jet and reaction forces. By means of fracture mechanics LBB for subcritical cracks has to be shown and the calculation of leakage areas is the basis for quantitatively determining the discharge rate of leaking subcritical through-wall cracks. The analytical approach and its validation will be presented for two examples of complex structures. The first one is a pipe branch containing a circumferential crack and the second one is a pipe bend with a longitudinal crack.

  20. Determining Surface Material Properties Using Satellite Imaging

    Science.gov (United States)

    Gloudeman, C.; Gerace, A. D.

    2017-12-01

    Knowledge of soil moisture content is necessary for drought monitoring, crop irrigation, and water runoff. Remote sensing techniques provide a more efficient alternative to traditional field measurements for determining soil moisture content. Thermal infrared sensors from Landsat, MODIS Aqua & Terra, and AVHRR MetOp A & B satellites were used to find thermal inertia, which is highly correlated with soil moisture. A diurnal cycle is converted from band effective radiance to Land Surface Temperature (LST) using Planck's Law for blackbody radiation and a modified split-window algorithm. The THERM model for finding expected LST is then used to determine the material properties. A second approach was used to calculate apparent thermal inertia and soil moisture content from day/ night pairs of LST. For this method, only the MODIS Aqua LST product was used.To this end, we have observed clear differences in moisture between areas of vegetation and sand and between different crop fields. Our results indicate that matching the observed data with the THERM model could be improved with increased satellite measurements.

  1. A method of determining surface runoff by

    Science.gov (United States)

    Donald E. Whelan; Lemuel E. Miller; John B. Cavallero

    1952-01-01

    To determine the effects of watershed management on flood runoff, one must make a reliable estimate of how much the surface runoff can be reduced by a land-use program. Since surface runoff is the difference between precipitation and the amount of water that soaks into the soil, such an estimate must be based on the infiltration capacity of the soil.

  2. DETERMINATION OF SURFACE CHARGE DENSITY OF α ...

    African Journals Online (AJOL)

    a

    dissociation of these groups, result into a pH dependent surface charge whose density can be measured by acid-base titration. The surface charge density determined by such method is essentially measured relative to the unknown condition of the oxide/liquid interface prior to reagent addition (i.e. at the point of zero ...

  3. Method for treatment of a surface area of steel

    NARCIS (Netherlands)

    Bhowmik, S.; Aaldert, P.J.

    2009-01-01

    The invention relates to a method for treatment of a surface area of steel by polishing said surface area and performing a plasma treatment of said surface area wherein the plasma treatment is performed at at least atmospheric conditions and wherein the plasma treatment is carried out at a power of

  4. Right to Left Ventricular Diameter Ratio ≥0.42 is the Warning Flag for Suspecting Atrial Septal Defect in Preschool Children: Age- and Body Surface Area-Related Reference Values Determined by M-Mode Echocardiography.

    Science.gov (United States)

    Hashimoto, Ikuo; Watanabe, Kazuhiro; Ichida, Fukiko

    2016-04-01

    It is not always easy to observe and screen atrial septal defects (ASD) using echocardiography. In addition, there are no established echocardiographic reference indices for screening patients with ASDs. We retrospectively reviewed our database and recruited 151 isolated ASD patients and 2769 healthy subjects. In total, 307 echocardiographic studies were performed for ASD patients. Surgical repairs were done in 75 of the ASD patients. The ratio of right to left ventricular end-diastolic dimensions (RVD/LVD), which was determined by M-mode echocardiography, was used as an index of RV dilatation. After obtaining age- and body surface area (BSA)-related RVD/LVD nomograms in healthy subjects, we calculated the z-scores of RVD/LVD for all subjects and obtained the optimal cut-off values to differentiate patients with ASD from healthy subjects. The optimal cut-off values were high in neonates and gradually decreased with an increase in the age and BSA, but were almost constant in children aged >4 years or whose BSA was >0.65 m(2). The cut-off values of RVD/LVD for suspected ASD were ≥0.42 in children aged >4 years or those whose BSA was >0.65 m(2). Those for an ASD operation were ≥0.46 in those whose BSA > 0.65 m(2). The RVD/LVD determined by M-mode echocardiography is a useful index to evaluate RV dilatation in patients with ASDs. The RVD/LVD ≥ 0.42 is the warning flag for suspecting ASD in preschool children and that ≥0.46 may be a clinical important sign to determine ASD operation.

  5. Molecularly-Limited Fractal Surface Area of Mineral Powders

    Directory of Open Access Journals (Sweden)

    Petr Jandacka

    2016-05-01

    Full Text Available The topic of the specific surface area (SSA of powders is not sufficiently described in the literature in spite of its nontrivial contribution to adsorption and dissolution processes. Fractal geometry provides a way to determine this parameter via relation SSA ~ x(D − 3s(2 − D, where x (m is the particle size and s (m is a scale. Such a relation respects nano-, micro-, or macro-topography on the surface. Within this theory, the fractal dimension 2 ≤ D < 3 and scale parameter s plays a significant role. The parameter D may be determined from BET or dissolution measurements on several samples, changing the powder particle sizes or sizes of adsorbate molecules. If the fractality of the surface is high, the SSA does not depend on the particle size distribution and vice versa. In this paper, the SSA parameter is analyzed from the point of view of adsorption and dissolution processes. In the case of adsorption, a new equation for the SSA, depending on the term (2 − D∙(s2 − sBET/sBET, is derived, where sBET and s2 are effective cross-sectional diameters for BET and new adsorbates. Determination of the SSA for the dissolution process appears to be very complicated, since the fractality of the surface may change in the process. Nevertheless, the presented equations have good application potential.

  6. Surface areas of fractally rough particles studied by scattering

    International Nuclear Information System (INIS)

    Hurd, A.J.; Schaefer, D.W.; Smith, D.M.; Ross, S.B.; Le Mehaute, A.; Spooner, S.

    1989-01-01

    The small-angle scattering from fractally rough surfaces has the potential to give information on the surface area at a given resolution. By use of quantitative neutron and x-ray scattering, a direct comparison of surface areas of fractally rough powders was made between scattering and adsorption techniques. This study supports a recently proposed correction to the theory for scattering from fractal surfaces. In addition, the scattering data provide an independent calibration of molecular adsorbate areas

  7. Nondestructive, stereological estimation of canopy surface area

    DEFF Research Database (Denmark)

    Wulfsohn, Dvora-Laio; Sciortino, Marco; Aaslyng, Jesper M.

    2010-01-01

    a canopy using the smooth fractionator, (ii) sampling of leaves from the selected plants using the fractionator, and (iii) area estimation of the sampled leaves using point counting. We apply this procedure to estimate the total area of a chrysanthemum (Chrysanthemum morifolium L.) canopy and evaluate both...

  8. Thermal Desorption Analysis of Effective Specific Soil Surface Area

    Science.gov (United States)

    Smagin, A. V.; Bashina, A. S.; Klyueva, V. V.; Kubareva, A. V.

    2017-12-01

    A new method of assessing the effective specific surface area based on the successive thermal desorption of water vapor at different temperature stages of sample drying is analyzed in comparison with the conventional static adsorption method using a representative set of soil samples of different genesis and degree of dispersion. The theory of the method uses the fundamental relationship between the thermodynamic water potential (Ψ) and the absolute temperature of drying ( T): Ψ = Q - aT, where Q is the specific heat of vaporization, and a is the physically based parameter related to the initial temperature and relative humidity of the air in the external thermodynamic reservoir (laboratory). From gravimetric data on the mass fraction of water ( W) and the Ψ value, Polyanyi potential curves ( W(Ψ)) for the studied samples are plotted. Water sorption isotherms are then calculated, from which the capacity of monolayer and the target effective specific surface area are determined using the BET theory. Comparative analysis shows that the new method well agrees with the conventional estimation of the degree of dispersion by the BET and Kutilek methods in a wide range of specific surface area values between 10 and 250 m2/g.

  9. SurfaceWater Source Protection Areas (SPAs)

    Data.gov (United States)

    Vermont Center for Geographic Information — Source Protection Area (SPA) boundaries have been located on RF 24000 & RF 25000 scale USGS topographic maps by Water Supply Division (DEC) and VT Dept of Health...

  10. Biofilm Surface Density Determines Biocide Effectiveness

    Directory of Open Access Journals (Sweden)

    Sara Bas

    2017-12-01

    Full Text Available High resistance of biofilms for chemical challenges is a serious industrial and medical problem. In this work a gradient of surface covered with biofilm has been produced and correlated to the effectiveness of different commercially available oxidative biocides. The results for thin Escherichia coli biofilms grown in rich media supplemented with glucose or lactose on glass or poly methyl methacrylate surfaces indicate that the effectiveness of hydrogen peroxide or chlorine dioxide and quaternary ammonium compounds is inversely proportional to the fraction of the surface covered with the biofilm. In areas where biofilm covered more than 90% of the available surface the biocide treatment was inefficient after 60 min of incubation. The combined effect of oxidant and surfactant increased the effectiveness of the biocide. On the other hand, the increased biofilm viscoelasticity reduced biocide effectiveness. The results emphasize differential biocide effectiveness depending on the fraction of the attached bacterial cells. The results suggest that biofilm biocide resistance is an acquired property that increases with biofilm maturation. The more dense sessile structures present lower log reductions compared to less dense ones.

  11. Overcoming the reference large-area sources non-uniformity in surface area monitor calibration

    Energy Technology Data Exchange (ETDEWEB)

    Junior, Iremar Alves S.; Siqueira, Paulo de T.D.; Xavier, Marcs; Nascimento, Eduardo do; Potiens, Maria da Penha A., E-mail: iremarjr@usp.br, E-mail: ptsiquei@ipen.br, E-mail: mxavier@ipen.br, E-mail: eduardon@ufba.br, E-mail: mppalbu@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    This paper describes a study using MCNP5 simulations, a Monte Carlo based radiation transport code, in order to evaluate the possibility of using reference large-area sources that do not meet the uniformity recommendations of the ISO 8769:2010 in surface contamination monitors calibration. {sup 14}C, {sup 36}Cl, {sup 99}Tc, {sup 137}Cs and {sup 90}Sr + {sup 90}Y large area reference sources were simulated as well as the setup and the detector probe. Simulations were carried out for both uniform and non-uniform surface distributions. In the case of uniform distribution, specific weights for each region were considered, as obtained in the uniformity evaluation measurements. To each simulation, it was considered the average number of signals generated in each detector probe, i.e., it was determined the fraction of stories depositing energy in the corresponding gas filled region of the detector. Simulations results show differences in detection efficiency values up to 15%. (author)

  12. The Surface Chemical Properties of Novel High Surface Area Solids ...

    African Journals Online (AJOL)

    during zeolite synthesis.22 Because raw fly ash has large quanti- ties of a host of elements, many of these will act as nucleation sites, which results in many small crystals rather than a few large ones. Acid etching removed the needle-like structures on the particle surfaces, revealing a porous underlying structure. (Fig. 1c).

  13. Surface Area Distribution Descriptor for object matching

    Directory of Open Access Journals (Sweden)

    Mohamed F. Gafar

    2010-07-01

    Full Text Available Matching 3D objects by their similarity is a fundamental problem in computer vision, computer graphics and many other fields. The main challenge in object matching is to find a suitable shape representation that can be used to accurately and quickly discriminate between similar and dissimilar shapes. In this paper we present a new volumetric descriptor to represent 3D objects. The proposed descriptor is used to match objects under rigid transformations including uniform scaling. The descriptor represents the object by dividing it into shells, acquiring the area distribution of the object through those shells. The computed areas are normalised to make the descriptor scale-invariant in addition to rotation and translation invariant. The effectiveness and stability of the proposed descriptor to noise and variant sampling density as well as the effectiveness of the similarity measures are analysed and demonstrated through experimental results.

  14. Why Do We Need the Derivative for the Surface Area?

    Science.gov (United States)

    Hristova, Yulia; Zeytuncu, Yunus E.

    2016-01-01

    Surface area and volume computations are the most common applications of integration in calculus books. When computing the surface area of a solid of revolution, students are usually told to use the frustum method instead of the disc method; however, a rigorous explanation is rarely provided. In this note, we provide one by using geometric…

  15. Determination effects of impervious areas on urban watershed.

    Science.gov (United States)

    Şimşek Uygun, Burcu; Albek, Mine

    2015-02-01

    After the industrial revolution, urban growth has been increasing, especially with technological advances. Urbanization is accelerating environmental pollution and also affects climate significantly because of land use or land cover changes. In this study, the Hydrological Simulation Program-Fortran (HSPF) model developed by the United States Environment Protection Agency (USEPA) is used for modeling the impervious areas of Eskişehir which is located in the Porsuk Stream Watershed in Inner Anatolia, Turkey. Effects of impervious areas of Eskisehir on the Porsuk Stream pollution between 1975 and 2010 have been investigated. Important water quality parameters like nitrate, orthophosphate, sediment, chloride, and total coliform are modeled. Impervious land segments have been found to be affecting all parameter concentrations and also surface flows significantly as determined using the t test with a confidence level of 95 %.

  16. The Effect of 200 MPa Pressure on Specific Surface Area of Clay

    Directory of Open Access Journals (Sweden)

    Koszela-Marek Ewa

    2015-02-01

    Full Text Available The paper presents the results of laboratory studies of the 200 MPa pressure effect on specific surface area of clay. The original high-pressure investigation stand was used for the pressure tests. Determination of the specific surface area was performed by the methylene blue adsorption method. The results of the specific surface area test were compared for non-pressurized clays and for clays pressured in a high-pressure chamber. It was found that the specific surface area of pressurized soil clearly increased. This shows that some microstructural changes take place in the soil skeleton of clays.

  17. 25 CFR 37.110 - Who determines geographic attendance areas?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Who determines geographic attendance areas? 37.110... BOUNDARIES All Schools § 37.110 Who determines geographic attendance areas? The Tribal governing body or the Secretary determines geographic attendance areas. ...

  18. Lage-area planar RF plasma productions by surface waves

    International Nuclear Information System (INIS)

    Nonaka, S.

    1994-01-01

    Large-area rf plasmas are confirmed to be produced by means of RF discharges inside a large-area dielectric tube. The plasma space is 73 cm x 176 cm and 2.5 cm. The plasma is thought to be produced by an odd plasma-surface wave (PSW ο ) in case of using large-area electrodes and by an even plasma-surface wave (PSW ο ) in case of without the electrodes. (author). 7 refs, 4 figs

  19. Indexing aortic valve area by body surface area increases the prevalence of severe aortic stenosis

    DEFF Research Database (Denmark)

    Jander, Nikolaus; Gohlke-Bärwolf, Christa; Bahlmann, Edda

    2014-01-01

    To account for differences in body size in patients with aortic stenosis, aortic valve area (AVA) is divided by body surface area (BSA) to calculate indexed AVA (AVAindex). Cut-off values for severe stenosis are......To account for differences in body size in patients with aortic stenosis, aortic valve area (AVA) is divided by body surface area (BSA) to calculate indexed AVA (AVAindex). Cut-off values for severe stenosis are...

  20. Environmental and geochemical assessment of surface sediments on irshansk ilmenite deposit area

    Directory of Open Access Journals (Sweden)

    Наталия Олеговна Крюченко

    2015-03-01

    Full Text Available It is revealed the problem of pollution of surface sediments of Irshansk ilmenite deposit area of various chemical elements hazard class (Mn, V, Ba, Ni, Co, Cr, Mo, Cu, Pb, Zn. It is determined its average content in surface sediments of various functional areas (forest and agricultural land, flood deposits, reclaimed land, calculated geochemical criteria, so given ecological and geochemical assessment of area

  1. Target surface area effects on hot electron dynamics from high intensity laser-plasma interactions

    Science.gov (United States)

    Zulick, C.; Raymond, A.; McKelvey, A.; Chvykov, V.; Maksimchuk, A.; Thomas, A. G. R.; Willingale, L.; Yanovsky, V.; Krushelnick, K.

    2016-06-01

    Reduced surface area targets were studied using an ultra-high intensity femtosecond laser in order to determine the effect of electron sheath field confinement on electron dynamics. X-ray emission due to energetic electrons was imaged using a {K}α imaging crystal. Electrons were observed to travel along the surface of wire targets, and were slowed mainly by the induced fields. Targets with reduced surface areas were correlated with increased hot electron densities and proton energies. Hybrid Vlasov-Fokker-Planck simulations demonstrated increased electric sheath field strength in reduced surface area targets.

  2. Effect of impervious surface area and vegetation changes on mean ...

    African Journals Online (AJOL)

    This land use or land cover changes are also thought to affect the climate of the Tshwane metropolis as is evidenced by heat waves in 2013 and 2014. This paper describes how vegetation and impervious surface area (ISA) or built up areas were classified from Landsat 8 LCDM, 2013, and Landsat 7 ETM+, 2003 images ...

  3. Measurement of the specific surface area of loose copper deposit by electrochemical methods

    Directory of Open Access Journals (Sweden)

    E. A. Dolmatova

    2016-07-01

    Full Text Available In the work the surface area of the electrode with dispersed copper deposit obtained within 30 seconds was evaluated by techniques of chronopotentiometry (CPM and impedance spectroscopy. In method CPM the electrode surface available for measurement depends on the value of the polarizing current. At high currents during the transition time there is a change of surface relief that can not determine the full surface of loose deposit. The electrochemical impedance method is devoid of this shortcoming since the measurements are carried out in indifferent electrolyte in the absence of current. The area measured by the impedance is tens of times higher than the value obtained by chronopotentiometry. It is found that from a solution containing sulfuric acid the deposits form with a high specific surface area. Based on these data it was concluded that the method of impedance spectroscopy can be used to measure in situ the surface area of the dispersed copper deposits.

  4. Surface area considerations for corroding N reactor fuel

    International Nuclear Information System (INIS)

    Johnson, A.B. Jr.; Pitner, A.L.

    1996-06-01

    The N Reactor fuel is corroding at sites where the Zircaloy cladding was damaged when the fuel was discharged from the reactor. Corroding areas are clearly visible on the fuel stored in open cans in the K East Basin. There is a need to estimate the area of the corroding uranium to analyze aspects of fuel behavior as it is transitioned. from current wet storage to dry storage. In this report, the factors that contribute to open-quotes trueclose quotes surface area are analyzed in terms of what is currently known about the N Reactor fuel. Using observations from a visual examinations of the fuel in the K East wet storage facility, a value for the corroding geometric area is estimated. Based on observations of corroding uranium and surface roughness values for other metals, a surface roughness factor is also estimated and applied to the corroding K East fuel to provide an estimated open-quotes trueclose quotes surface area. While the estimated area may be modified as additional data become available from fuel characterization studies, the estimate provides a basis to assess effects of exposed uranium metal surfaces on fuel behavior in operations involved in transitioning from wet to dry storage, during shipment and staging, conditioning, and dry interim storage

  5. Assessment of dialyzer surface in online hemodiafiltration; objective choice of dialyzer surface area

    Directory of Open Access Journals (Sweden)

    Francisco Maduell

    2015-05-01

    Conclusion: The increase in 40% and 80% of dialyzer surface area entails an increase in convective volume of 6 and 16% respectively, showing minimal differences both in convective volume and clearance capacity when UFC was greater than 45 mL/h/mmHg. It is advisable to optimise dialyser efficiency to the smallest surface area possible, adjusting treatment prescription.

  6. Students' and Teachers' Application of Surface Area to Volume Relationships

    Science.gov (United States)

    Taylor, Amy R.; Jones, M. Gail

    2013-02-01

    The National Science Education Standards emphasize teaching unifying concepts and processes such as basic functions of living organisms, the living environment, and scale (NRC 2011). Scale includes understanding that different characteristics, properties, or relationships within a system might change as its dimensions are increased or decreased (NRC 2011). One such relationship involves surface area to volume which is a pervasive concept that can be found throughout different sciences. This concept is important for students to not only understand the association of the two, but to also be able to apply this relationship in science contexts. The purpose of this study is to investigate the factors that influence the understanding surface area to volume relationships. This study examined middle school students', high school students', and science teachers' logical thinking skills (including proportional reasoning), visual-spatial skills, and understandings of surface area to volume relationships. Regression results indicated that participants' reasoning abilities and components of visual-spatial skills could be possible predictors for one's ability to understand surface area to volume relationships. Implications for teaching scale concepts such as surface area to volume relationships in the science classroom are discussed.

  7. Surface deformation of the secondary former mining areas

    Directory of Open Access Journals (Sweden)

    Tadeusz Głowacki

    2013-09-01

    Full Text Available The paper discuss the problem of secondary deformation observed on the surface of the land in the area of the old, non-existent copper and coal mines. The authors discuss the formation of the deformation in the final period of the mine, and after his arrest, after the close of any work of protecting the surface area of influence of mining activities. Discusses the reduction of the surface of the example of two disused mines: mining copper “Konrad” in Iwiny and “Thorez” in Walbrzych, an old coal mine. In the first part of the paper discusses a brief history of the creation of old copper basin and the Lower Silesian coal basin. It then discusses the formation of deformation processes in mining areas. Conducting continuous surveying allows you to monitor changes in the formation of land, in the paper indicate the source of the vertical displacements after ending of operation, the closure of the mine and stopped all work safety. In the area of Lower Silesia there are many remnants of disused mines, surface geodetic measurements show a constant activity in post-mining areas and the need to control the formation of the surface.

  8. DETERMINATION OF SURFACE CHARGE DENSITY OF α ...

    African Journals Online (AJOL)

    a

    . ... include manufacture of aerospace housing, automotive and jet engines and lead acid batteries. [2]. In specialised ... diameter of one hydrated ion) from the surface of the oxide (ψd) are normally measured through methods such as ...

  9. High surface area electrode for high efficient microbial electrosynthesis

    Science.gov (United States)

    Nie, Huarong; Cui, Mengmeng; Lu, Haiyun; Zhang, Tian; Russell, Thomas; Lovley, Derek

    2012-02-01

    Microbial electrosynthesis, a process in which microorganisms directly accept electrons from an electrode to convert carbon dioxide and water into multi carbon organic compounds, affords a novel route for the generation of valuable products from electricity or even wastewater. The surface area of the electrode is critical for high production. A biocompatible, highly conductive, three-dimensional cathode was fabricated from a carbon nanotube textile composite to support the microorganism to produce acetate from carbon dioxide. The high surface area and macroscale porous structure of the intertwined CNT coated textile ?bers provides easy microbe access. The production of acetate using this cathode is 5 fold larger than that using a planar graphite electrode with the same volume. Nickel-nanowire-modified carbon electrodes, fabricated by microwave welding, increased the surface area greatly, were able to absorb more bacteria and showed a 1.5 fold increase in performance

  10. OBSERVED ASTEROID SURFACE AREA IN THE THERMAL INFRARED

    Energy Technology Data Exchange (ETDEWEB)

    Nugent, C. R. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Mainzer, A.; Masiero, J.; Bauer, J.; Kramer, E.; Sonnett, S. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Wright, E. L. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Grav, T. [Planetary Science Institute, Tucson, AZ (United States)

    2017-02-01

    The rapid accumulation of thermal infrared observations and shape models of asteroids has led to increased interest in thermophysical modeling. Most of these infrared observations are unresolved. We consider what fraction of an asteroid’s surface area contributes the bulk of the emitted thermal flux for two model asteroids of different shapes over a range of thermal parameters. The resulting observed surface in the infrared is generally more fragmented than the area observed in visible wavelengths, indicating high sensitivity to shape. For objects with low values of the thermal parameter, small fractions of the surface contribute the majority of thermally emitted flux. Calculating observed areas could enable the production of spatially resolved thermal inertia maps from non-resolved observations of asteroids.

  11. STEREOLOGICAL ESTIMATION OF SURFACE AREA FROM DIGITAL IMAGES

    Directory of Open Access Journals (Sweden)

    Johanna Ziegel

    2011-05-01

    Full Text Available A sampling design of local stereology is combined with a method from digital stereology to yield a novel estimator of surface area based on counts of configurations observed in a digitization of an isotropic 2- dimensional slice with thickness s. As a tool, a result of the second author and J. Rataj on infinitesimal increase of volumes of morphological transforms is refined and used. The proposed surface area estimator is asymptotically unbiased in the case of sets contained in the ball centred at the origin with radius s and in the case of balls centred at the origin with unknown radius. For general shapes bounds for the asymptotic expected relative worst case error are given. A simulation example is discussed for surface area estimation based on 2×2×2-configurations.

  12. Surface Area, and Oxidation Effects on Nitridation Kinetics of Silicon Powder Compacts

    Science.gov (United States)

    Bhatt, R. T.; Palczer, A. R.

    1998-01-01

    Commercially available silicon powders were wet-attrition-milled from 2 to 48 hr to achieve surface areas (SA's) ranging from 1.3 to 70 sq m/g. The surface area effects on the nitridation kinetics of silicon powder compacts were determined at 1250 or 1350 C for 4 hr. In addition, the influence of nitridation environment, and preoxidation on nitridation kinetics of a silicon powder of high surface area (approximately equals 63 sq m/g) was investigated. As the surface area increased, so did the percentage nitridation after 4 hr in N2 at 1250 or 1350 C. Silicon powders of high surface area (greater than 40 sq m/g) can be nitrided to greater than 70% at 1250 C in 4 hr. The nitridation kinetics of the high-surface-area powder compacts were significantly delayed by preoxidation treatment. Conversely, the nitridation environment had no significant influence on the nitridation kinetics of the same powder. Impurities present in the starting powder, and those accumulated during attrition milling, appeared to react with the silica layer on the surface of silicon particles to form a molten silicate layer, which provided a path for rapid diffusion of nitrogen and enhanced the nitridation kinetics of high surface area silicon powder.

  13. Groundwater Quality Assessment for Waste Management Area U: First Determination

    Energy Technology Data Exchange (ETDEWEB)

    FN Hodges; CJ Chou

    2000-08-04

    Waste Management Area U (TWA U) is located in the 200 West Area of the Hanford Site. The area includes the U Tank Farm, which contains 16 single-shell tanks and their ancillary equipment and waste systems. WMA U is regulated under the Resource Conservation and Recovery Act of 1976 (RCRA) as stipulated in 40 CFR Part 265, Subpart F, which is incorporated into the Washington State dangerous waste regulations (WAC 173-303400) by reference. Groundwater monitoring at WMA U has been guided by an interim status indicator evaluation program. As a result of changes in the direction of groundwater flow, background values for the WMA have been recalculated several times during its monitoring history. The most recent recalculation revealed that one of the indicator parameters, specific conductance, exceeded its background value in downgradient well 299-W19-41. This triggered a change from detection monitoring to a groundwater quality assessment program. The major contributors to the higher specific conductance are nonhazardous constituents, such as bicarbonate, calcium, chloride, magnesium, sodium and sulfate. Chromium, nitrate, and technetium-99 are present and are increasing; however, they are significantly below their drinking water standards. The objective of this study is to determine whether the increased concentrations of chromium, nitrate, and technetium-99 in groundwater are from WMA U or from an upgradient source. Interpretation of groundwater monitoring data indicates that both the nonhazardous constituents causing elevated specific conductance in groundwater and the tank waste constituents present in groundwater at the WMA are a result of surface water infiltration in the southern portion of the WMA. There is evidence that both upgradient and WMA sources contribute to the nitrate concentrations that were detected. There is no indication of an upgradient source for the chromium and technetium-99 that was detected. Therefore, a source of contamination appears to

  14. Groundwater Quality Assessment for Waste Management Area U: First Determination

    International Nuclear Information System (INIS)

    FN Hodges; CJ Chou

    2000-01-01

    Waste Management Area U (TWA U) is located in the 200 West Area of the Hanford Site. The area includes the U Tank Farm, which contains 16 single-shell tanks and their ancillary equipment and waste systems. WMA U is regulated under the Resource Conservation and Recovery Act of 1976 (RCRA) as stipulated in 40 CFR Part 265, Subpart F, which is incorporated into the Washington State dangerous waste regulations (WAC 173-303400) by reference. Groundwater monitoring at WMA U has been guided by an interim status indicator evaluation program. As a result of changes in the direction of groundwater flow, background values for the WMA have been recalculated several times during its monitoring history. The most recent recalculation revealed that one of the indicator parameters, specific conductance, exceeded its background value in downgradient well 299-W19-41. This triggered a change from detection monitoring to a groundwater quality assessment program. The major contributors to the higher specific conductance are nonhazardous constituents, such as bicarbonate, calcium, chloride, magnesium, sodium and sulfate. Chromium, nitrate, and technetium-99 are present and are increasing; however, they are significantly below their drinking water standards. The objective of this study is to determine whether the increased concentrations of chromium, nitrate, and technetium-99 in groundwater are from WMA U or from an upgradient source. Interpretation of groundwater monitoring data indicates that both the nonhazardous constituents causing elevated specific conductance in groundwater and the tank waste constituents present in groundwater at the WMA are a result of surface water infiltration in the southern portion of the WMA. There is evidence that both upgradient and WMA sources contribute to the nitrate concentrations that were detected. There is no indication of an upgradient source for the chromium and technetium-99 that was detected. Therefore, a source of contamination appears to

  15. High surface area carbon and process for its production

    Energy Technology Data Exchange (ETDEWEB)

    Romanos, Jimmy; Burress, Jacob; Pfeifer, Peter; Rash, Tyler; Shah, Parag; Suppes, Galen

    2016-12-13

    Activated carbon materials and methods of producing and using activated carbon materials are provided. In particular, biomass-derived activated carbon materials and processes of producing the activated carbon materials with prespecified surface areas and pore size distributions are provided. Activated carbon materials with preselected high specific surface areas, porosities, sub-nm (<1 nm) pore volumes, and supra-nm (1-5 nm) pore volumes may be achieved by controlling the degree of carbon consumption and metallic potassium intercalation into the carbon lattice during the activation process.

  16. Surface barrier silicon detectors with a large active area

    International Nuclear Information System (INIS)

    Kim, Y.; Husimi, K.; Ikeda, Y.; Kim, C.; Ohkawa, S.; Sakai, T.

    1985-01-01

    Surface barrier silicon detectors with a large active area have been produced by using high resistive n-type silicon crystals, diameters of which are 3 to 5 inches. High quality detectors with a low leakage current and a low noise were achieved by developing the improved surface treatment. Characteristics of detectors obtained are good in energy resolution compared with conventional large area Si(Li) detectors. It has also been confirmed that local dead region is not found from measuring results of photo-pulse injection

  17. Stereological estimation of surface area from digital images

    DEFF Research Database (Denmark)

    Ziegel, Johanna; Kiderlen, Markus

    2010-01-01

    A sampling design of local stereology is combined with a method from digital stereology to yield a novel estimator of surface area based on counts of configurations observed in a digitization of an isotropic 2- dimensional slice with thickness s. As a tool, a result of the second author and J....... Rataj on infinitesimal increase of volumes of morphological transforms is refined and used. The proposed surface area estimator is asymptotically unbiased in the case of sets contained in the ball centred at the origin with radius s and in the case of balls centred at the origin with unknown radius...

  18. DETERMINATION OF IMPORTANCE EVALUATION FOR THE SURFACE EXPLORATORY STUDIES FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    C.J. Byrne

    2000-07-25

    This DIE applies to the surface facilities component of the Yucca Mountain Site Characterization Project (W) ESF. The ESF complex-including surface and subsurface accommodations--encompasses an area that is approximately six miles wide and nine miles long (approximately 30,000 acres total) (United States Department of Energy [DOE] 1997, p. 9.04). It is located on federally withdrawn lands, near the southwest border of the Nevada Test Site (NTS) in southern Nevada (DOE 1997, p. 9.04). Site characterization activities are conducted within the subsurface ESF to obtain the information necessary to determine whether the Yucca Mountain Site is suitable as a geologic repository for spent nuclear fuel and high-level radioactive waste. Most ESF surface facilities are located within the Conceptual Controlled Area Boundary (CCAB) (DOE 1997, p. 9.04), with the exception of the southeastern most portions of the H-Road and the Water Supply System. Various SBT activities are also conducted throughout the Yucca Mountain region as a part of the overall site-characterization effort. In general, the DIE for SBT Activities (Civilian Radioactive Waste Management System [CRWMS] Management and Operating Contractor [M&O] 1998a) evaluates activities associated with SBT. Potential test-to-test interference and waste isolation impacts associated with SBT activities are also evaluated in CRWMS M&O (1998a).

  19. DETERMINATION OF IMPORTANCE EVALUATION FOR THE SURFACE EXPLORATORY STUDIES FACILITY

    International Nuclear Information System (INIS)

    C.J. Byrne

    2000-01-01

    This DIE applies to the surface facilities component of the Yucca Mountain Site Characterization Project (W) ESF. The ESF complex-including surface and subsurface accommodations--encompasses an area that is approximately six miles wide and nine miles long (approximately 30,000 acres total) (United States Department of Energy [DOE] 1997, p. 9.04). It is located on federally withdrawn lands, near the southwest border of the Nevada Test Site (NTS) in southern Nevada (DOE 1997, p. 9.04). Site characterization activities are conducted within the subsurface ESF to obtain the information necessary to determine whether the Yucca Mountain Site is suitable as a geologic repository for spent nuclear fuel and high-level radioactive waste. Most ESF surface facilities are located within the Conceptual Controlled Area Boundary (CCAB) (DOE 1997, p. 9.04), with the exception of the southeastern most portions of the H-Road and the Water Supply System. Various SBT activities are also conducted throughout the Yucca Mountain region as a part of the overall site-characterization effort. In general, the DIE for SBT Activities (Civilian Radioactive Waste Management System [CRWMS] Management and Operating Contractor [M andO] 1998a) evaluates activities associated with SBT. Potential test-to-test interference and waste isolation impacts associated with SBT activities are also evaluated in CRWMS M andO (1998a)

  20. Dynamic characterisation of the specific surface area for fracture networks

    Science.gov (United States)

    Cvetkovic, V.

    2017-12-01

    One important application of chemical transport is geological disposal of high-level nuclear waste for which crystalline rock is a prime candidate for instance in Scandinavia. Interconnected heterogeneous fractures of sparsely fractured rock such as granite, act as conduits for transport of dissolved tracers. Fluid flow is known to be highly channelized in such rocks. Channels imply narrow flow paths, adjacent to essentially stagnant water in the fracture and/or the rock matrix. Tracers are transported along channelised flow paths and retained by minerals and/or stagnant water, depending on their sorption properties; this mechanism is critical for rocks to act as a barrier and ultimately provide safety for a geological repository. The sorbing tracers are retained by diffusion and sorption on mineral surfaces, whereas non-sorbing tracers can be retained only by diffusion into stagnant water of fractures. The retention and transport properties of a sparsely fractured rock will primarily depend on the specific surface area (SSA) of the fracture network which is determined by the heterogeneous structure and flow. The main challenge when characterising SSA on the field-scale is its dependence on the flow dynamics. We first define SSA as a physical quantity and clarify its importance for chemical transport. A methodology for dynamic characterisation of SSA in fracture networks is proposed that relies on three sets of data: i) Flow rate data as obtained by a flow logging procedure; ii) transmissivity data as obtained by pumping tests; iii) fracture network data as obtained from outcrop and geophysical observations. The proposed methodology utilises these data directly as well as indirectly through flow and particle tracking simulations in three-dimensional discrete fracture networks. The methodology is exemplified using specific data from the Swedish site Laxemar. The potential impact of uncertainties is of particular significance and is illustrated for radionuclide

  1. Relationship between Mineral Soil Surface Area and the Biological Degradation of Biosolids Added to Soil

    Directory of Open Access Journals (Sweden)

    Dongqi Wen

    2015-12-01

    Full Text Available Geochemical and biological processes that operate in the soil matrix and on the soil surface are important to the degradation of biosolids in soil. Due to the large surface area of soils it is assumed that the microbial ecology is associated with mineral soil surface area. The total mineral surface areas were determined for soils from eight different fields selected from a long term study (1972–2006 of annual biosolids application to 41 fields in central Illinois varying in size from 3.6 to 66 ha. The surface areas for the soils varied from 1 to 9 m2/g of soil. The biological degradation rates for the eight soils were determined using a biological degradation rate model (DRM and varied from 0.02 to 0.20/year−1. Regression analysis revealed that the degradation rate was positively associated with mineral soil surface area (1 m2/g produces 0.018 year−1 increase in the degradation rate. The annual soil sequestration rate was calculated to increase from 1% to 6% when the soil total surface area increased from 1 to 9 m2/g of soil. Therefore, land application of biosolids is an effective way to enhance carbon sequestration in soils and reduce greenhouse gas emissions.

  2. Determination of the surface drag coefficient

    DEFF Research Database (Denmark)

    Mahrt, L.; Vickers, D.; Sun, J.L.

    2001-01-01

    This study examines the dependence of the surface drag coefficient on stability, wind speed, mesoscale modulation of the turbulent flux and method of calculation of the drag coefficient. Data sets over grassland, sparse grass, heather and two forest sites are analyzed. For significantly unstable ...

  3. Clay mineralogy in different geomorphic surfaces in sugarcane areas

    Science.gov (United States)

    Camargo, L.; Marques, J., Jr.

    2012-04-01

    The crystallization of the oxides and hydroxides of iron and aluminum and kaolinite of clay fraction is the result of pedogenetic processes controlled by the relief. These minerals have influence on the physical and chemical attributes of soil and exhibit spatial dependence. The pattern of spatial distribution is influenced by forms of relief as the geomorphic surfaces. In this sense, the studies aimed at understanding the relationship between relief and the distribution pattern of the clay fraction attributes contribute to the delineation of specific areas of management in the field. The objective of this study was to evaluate the spatial distribution of oxides and hydroxides of iron and aluminum and kaolinite of clay fraction and its relationship with the physical and chemical attributes in different geomorphic surfaces. Soil samples were collected in a transect each 25 m (100 samples) and in the sides of the same (200 samples) as well as an area of 500 ha (1 sample each six hectare). Geomorphic surfaces (GS) in the transect were mapped in detail to support mapping the entire area. The soil samples were taken to the laboratory for chemical, physical, and mineralogical analysis, and the pattern of spatial distribution of soil attributes was obtained by statistics and geostatistics. The GS I is considered the oldest surface of the study area, with depositional character, and a slope ranging from 0 to 4%. GS II and III are considered to be eroded, and the surface II plan a gentle slope that extends from the edge of the surface until the beginning of I and III. The crystallographic characteristics of the oxides and hydroxides of iron and aluminum and kaolinite showed spatial dependence and the distribution pattern corresponding to the limits present of the GS in the field. Surfaces I and II showed the best environments to the degree of crystallinity of hematite and the surface III to the greatest degree of crystallinity of goethite agreeing to the pedoenvironment

  4. Indexing Glomerular Filtration Rate to Body Surface Area

    DEFF Research Database (Denmark)

    Redal-Baigorri, Belén; Rasmussen, Knud; Heaf, James Goya

    2014-01-01

    BACKGROUND: Kidney function is mostly expressed in terms of glomerular filtration rate (GFR). A common feature is the expression as ml/min per 1.73 m(2) , which represents the adjustment of the individual kidney function to a standard body surface area (BSA) to allow comparison between individuals...

  5. Plasma Creatinine, Age and Body Surface Area in Nigerian Children ...

    African Journals Online (AJOL)

    In a bid to establish reference values for plasma creatinine in children and adolescents using age, and body surface area (BSA), 462 apparently healthy Nigerian children/adolescents aged one day to 15 years were studied. They were recruited from well baby clinics, as well as primary and secondary schools. Plasma ...

  6. Evaluation of five formulae for estimating body surface area of ...

    African Journals Online (AJOL)

    Background: Physiological functions are often assessed by standardizing for body surface area (BSA) to avoid excessive variation in calculations in pediatric practice. Aim: To explore the suitability of existing formulae for estimating the BSA of Nigerian children. Subjects and Methods: This cross‑sectional study involved ...

  7. (Impervious) Surfaces on the Microclimate of Urban Area

    African Journals Online (AJOL)

    The present paper shows the considerable impacts of both vegetated and synthetic surfaces on the microclimate of urban area. Vegetation of a particular place affects the microclimate through reduced solar radiation and lower air temperature due to shading and evapotranspiration. Lower air temperatures are essential ...

  8. Installation and performance evaluation of an indigenous surface area analyser

    International Nuclear Information System (INIS)

    Pillai, S.N.; Solapurkar, M.N.; Venkatesan, V.; Prakash, A.; Khan, K.B.; Kumar, Arun; Prasad, R.S.

    2014-01-01

    An indigenously available surface area analyser was installed inside glove box and checked for its performance by analyzing uranium oxide and thorium oxide powders at RMD. The unit has been made ready for analysis of Plutonium oxide powders after incorporating several important features. (author)

  9. Influence of Ear Surface Area on Heat Tolerance of Composite ...

    African Journals Online (AJOL)

    Low correlation (r = 0.12) was observed between body weight and ear width. There were no correlations between ear width, respiratory rates and pulse rate. However, a residual correlation (r = -0.03) was obtained between ear width and body temperature. Large ear surface area in composite rabbits enhances better ...

  10. Assessment of large aperture scintillometry for large-area surface ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 126; Issue 5. Assessment of large aperture scintillometry for large-area surface energy fluxes over an irrigated cropland in north India. Abhishek Danodia V K Sehgal N R Patel R Dhakar J Mukherjee S K Saha A Senthil Kumar. Volume 126 Issue 5 July 2017 Article ...

  11. Surface water and groundwater interaction in Marala - Khanki area, Punjab

    International Nuclear Information System (INIS)

    Akram, W.; Ahmad, M.; Latif, Z.; Tariq, J.A.; Malik, M.R.

    2011-07-01

    Isotope hydrological investigations were carried out in two selected areas of Indus Basin viz. Haripur Area and Chashma- Taunsa Area for elucidating various aspects of surface water and groundwater interaction. Groundwater samples were collected on seasonal basis (low and high river discharge periods) while surface water samples were collected more frequently (weekly or monthly basis). Isotopic data suggested that there is no contribution of surface water to groundwater recharge in Haripur Area and rain is the prevailing source of groundwater recharge. The data further revealed that isotopic values of the Haripur pocket of Tarbela Lake are higher than those of Main Lake / Indus River meaning that there is a significant contribution of base flow in this pocket. Indus River appeared to be the dominant source of groundwater recharge at most of the locations in Chashma- Taunsa Area. Isotopic data of Indus River showed an increase at Taunsa as compared to Chashma in low flow period indicating the high contribution of base flow at this point in time. Stable isotopes were successfully used to quantify the base flow contribution. (author)

  12. Growth of contact area between rough surfaces under normal stress

    Science.gov (United States)

    Stesky, R. M.; Hannan, S. S.

    1987-05-01

    The contact area between deforming rough surfaces in marble, alabaster, and quartz was measured from thin sections of surfaces bonded under load with low viscosity resin epoxy. The marble and alabaster samples had contact areas that increased with stress at an accelerating rate. This result suggests that the strength of the asperity contacts decreased progressively during the deformation, following some form of strain weakening relationship. This conclusion is supported by petrographic observation of the thin sections that indicate that much of the deformation was cataclastic, with minor twinning of calcite and kinking of gypsum. In the case of the quartz, the observed contact area was small and increased approximately linearly with normal stress. Only the irreversible cataclastic deformation was observed; however strain-induced birefringence and cracking of the epoxy, not observed with the other rocks, suggests that significant elastic deformation occurred, but recovered during unloading.

  13. Empirical Determination of Competence Areas to Computer Science Education

    Science.gov (United States)

    Zendler, Andreas; Klaudt, Dieter; Seitz, Cornelia

    2014-01-01

    The authors discuss empirically determined competence areas to K-12 computer science education, emphasizing the cognitive level of competence. The results of a questionnaire with 120 professors of computer science serve as a database. By using multi-dimensional scaling and cluster analysis, four competence areas to computer science education…

  14. Determination of Energy Fluxes Over Agricultural Surfaces

    Directory of Open Access Journals (Sweden)

    Josefina Argete

    1994-12-01

    Full Text Available An energy budget was conducted over two kinds if surfaces: grass and corn canopy. The net radiative flux and the soil heat flux were directly measured while the latent and sensible heat flux were calculated from the vertical profiles if wet and dry-bulb temperature and wind speed. The crop storage flux was also estimated. Using the gradient or aerodynamic equations, the calculated fluxes when compared to the measured fluxes in the context of an energy budget gave an SEE = 63 Wm-2 over grass and SEE = 81 Wm-2 over corn canopy. The calculated fluxes compared reasonably well with those obtained using the Penman equations.For an energy budget research with limited instrumentation, the aerodynamic method performed satisfactorily in estimating the daytime fluxes, when atmospheric conditions are fully convective, but failed when conditions were stably stratified as during nighttime.

  15. Rapid fabrication of large-area, corrosion-resistant superhydrophobic Mg alloy surfaces.

    Science.gov (United States)

    Xu, Wenji; Song, Jinlong; Sun, Jing; Lu, Yao; Yu, Ziyuan

    2011-11-01

    A superhydrophobic magnesium (Mg) alloy surface was successfully fabricated via a facile electrochemical machining process, and subsequently covered with a fluoroalkylsilane (FAS) film. The surface morphologies and chemical compositions were investigated using a scanning electron microscope (SEM) equipped with an energy-dispersive spectroscopy (EDS) and a Fourier-transform infrared spectrophotometer (FTIR). The results show hierarchal rough structures and an FAS film with a low surface energy on the Mg alloy surfaces, which confers good superhydrophobicity with a water contact angle of 165.2° and a water tilting angle of approximately 2°. The processing conditions, such as the processing time and removal rate per unit area at a constant removal mass per unit area, were investigated to determine their effects on the superhydrophobicity. Interestingly, when the removal mass per unit area is constant at approximately 11.10 mg/cm(2), the superhydrophobicity does not change with the removal rate per unit area. Therefore, a superhydrophobic Mg alloy surface can be rapidly fabricated based on this property. A large-area superhydrophobic Mg alloy surface was also fabricated for the first time using a small-area moving cathode. The corrosion resistance and durability of the superhydrophobic surfaces were also examined.

  16. Determining the surface roughness coefficient by 3D Scanner

    Directory of Open Access Journals (Sweden)

    Karmen Fifer Bizjak

    2010-12-01

    Full Text Available Currently, several test methods can be used in the laboratory to determine the roughness of rock joint surfaces.However, true roughness can be distorted and underestimated by the differences in the sampling interval of themeasurement methods. Thus, these measurement methods produce a dead zone and distorted roughness profiles.In this paper a new rock joint surface roughness measurement method is presented, with the use of a camera-typethree-dimensional (3D scanner as an alternative to current methods. For this study, the surfaces of ten samples oftuff were digitized by means of a 3D scanner, and the results were compared with the corresponding Rock JointCoefficient (JRC values. Up until now such 3D scanner have been mostly used in the automotive industry, whereastheir use for comparison with obtained JRC coefficient values in rock mechanics is presented here for the first time.The proposed new method is a faster, more precise and more accurate than other existing test methods, and is apromising technique for use in this area of study in the future.

  17. Facility effluent monitoring plan determinations for the 400 Area facilities

    International Nuclear Information System (INIS)

    Nickels, J.M.

    1991-09-01

    This Facility Effluent Monitoring Plan determination resulted from an evaluation conducted for the Westinghouse Hanford Company 400 Area facilities on the Hanford Site. The Facility Effluent Monitoring Plan determinations have been prepared in accordance with A Guide for Preparing Hanford Site Facility Effluent Monitoring Plans. Two major Westinghouse Hanford Company facilities in the 400 Area were evaluated: the Fast Flux Test Facility and the Fuels Manufacturing and examination Facility. The determinations were prepared by Westinghouse Hanford Company. Of these two facilities, only the Fast Flux Test Facility will require a Facility Effluent Monitoring Plan. 7 refs., 5 figs., 4 tabs

  18. Tropical cyclone rainfall area controlled by relative sea surface temperature.

    Science.gov (United States)

    Lin, Yanluan; Zhao, Ming; Zhang, Minghua

    2015-03-12

    Tropical cyclone rainfall rates have been projected to increase in a warmer climate. The area coverage of tropical cyclones influences their impact on human lives, yet little is known about how tropical cyclone rainfall area will change in the future. Here, using satellite data and global atmospheric model simulations, we show that tropical cyclone rainfall area is controlled primarily by its environmental sea surface temperature (SST) relative to the tropical mean SST (that is, the relative SST), while rainfall rate increases with increasing absolute SST. Our result is consistent with previous numerical simulations that indicated tight relationships between tropical cyclone size and mid-tropospheric relative humidity. Global statistics of tropical cyclone rainfall area are not expected to change markedly under a warmer climate provided that SST change is relatively uniform, implying that increases in total rainfall will be confined to similar size domains with higher rainfall rates.

  19. Spectral theory of infinite-area hyperbolic surfaces

    CERN Document Server

    Borthwick, David

    2016-01-01

    This text introduces geometric spectral theory in the context of infinite-area Riemann surfaces, providing a comprehensive account of the most recent developments in the field. For the second edition the context has been extended to general surfaces with hyperbolic ends, which provides a natural setting for development of the spectral theory while still keeping technical difficulties to a minimum. All of the material from the first edition is included and updated, and new sections have been added. Topics covered include an introduction to the geometry of hyperbolic surfaces, analysis of the resolvent of the Laplacian, scattering theory, resonances and scattering poles, the Selberg zeta function, the Poisson formula, distribution of resonances, the inverse scattering problem, Patterson-Sullivan theory, and the dynamical approach to the zeta function. The new sections cover the latest developments in the field, including the spectral gap, resonance asymptotics near the critical line, and sharp geometric constan...

  20. Influence of Ecological Factors on Estimation of Impervious Surface Area Using Landsat 8 Imagery

    Directory of Open Access Journals (Sweden)

    Yuqiu Jia

    2017-07-01

    Full Text Available Estimation of impervious surface area is important to the study of urban environments and social development, but surface characteristics, as well as the temporal, spectral, and spatial resolutions of remote sensing images, influence the estimation accuracy. To investigate the effects of regional environmental characteristics on the estimation of impervious surface area, we divided China into seven sub-regions based on climate, soil type, feature complexity, and vegetation phenology: arid and semi-arid areas, Huang-Huai-Hai winter wheat production areas, typical temperate regions, the Pearl River Delta, the middle and lower reaches of the Yangtze River, typical tropical and subtropical regions, and the Qinghai Tibet Plateau. Impervious surface area was estimated from Landsat 8 images of five typical cities, including Yinchuan, Shijiazhuang, Shenyang, Ningbo, and Kunming. Using the linear spectral unmixing method, impervious and permeable surface areas were determined at the pixel-scale based on end-member proportions. We calculated the producer’s accuracy, user’s accuracy, and overall accuracy to assess the estimation accuracy, and compared the accuracies among images acquired from different seasons and locations. In tropical and subtropical regions, vegetation canopies can confound the identification of impervious surfaces and, thus, images acquired in winter, early spring, and autumn are most suitable; estimations in the Pearl River Delta, the middle and lower reaches of the Yangtze River are influenced by soil, vegetation phenology, vegetation canopy, and water, and images acquired in spring, summer, and autumn provide the best results; in typical temperate areas, images acquired from spring to autumn are most effective for estimations; in winter wheat-growing areas, images acquired throughout the year are suitable; and in arid and semi-arid areas, summer and early autumn, during which vegetation is abundant, are the optimal seasons for

  1. Solvent accessible surface area (ASA) of simulated phospholipid membranes

    DEFF Research Database (Denmark)

    Tuchsen, E.; Jensen, Morten Østergaard; Westh, P.

    2003-01-01

    The membrane-solvent interface has been investigated through calculations of the solvent accessible surface area (ASA) for simulated membranes of DPPC and POPE. For DPPC at 52 degreesC we found an ASA of 126 +/- 8 Angstrom(2) per lipid molecule, equivalent to twice the projected lateral area......, even the most exposed parts of the PC head-group show average ASAs of less than half of its maximal or 'fully hydrated' value. The average ASA of a simulated POPE membrane was 96 +/- 7 Angstrom(2) per lipid. The smaller value than for DPPC reflects much lower ASA of the ammonium ion, which is partially...... compensated by increased exposure of the ethylene and phosphate moieties. The ASA of the polar moieties Of (PO4, NH3 and COO) constitutes 65% of the total accessible area for POPE, making this interface more polar than that of DPPC. It is suggested that ASA information can be valuable in attempts...

  2. Facility effluent monitoring plan determinations for the 100 Area facilities

    International Nuclear Information System (INIS)

    Brendel, D.E.

    1991-11-01

    The determination for Facility Effluent Monitoring Plans arose from evaluations conducted for the Westinghouse Hanford Company 100 Area facilities on the Hanford Site. The Facility Effluent Monitoring Plant determinations have been prepared in accordance with A Guide for Preparing Hanford Site Facility Effluent Monitoring Plan, WHC-EP-0438 (WHC 1991). Ten Westinghouse Hanford Company facilities in the 100 Areas were evaluated: N Reactor, KE/KW Reactors, 1706 KE Laboratory, and the Surplus Reactors (B, C, D, DR, F, and H). The N Reactor, KE/KW Reactors, and 1706 KE Laboratory Facility Effluent Monitoring Plan determinations were prepared by Columbia Energy and Environmental Services of Richland, Washington. The determination for the Surplus Reactors was prepared by Westinghouse Hanford Company. Of the 10 facilities evaluated, two will require a Facility Effluent Monitoring Plan: N Reactor and the active spent fuel storage facilities and their contiguous support facilities at 100 KE and 100 KW

  3. Possibilities of surface waters monitoring at mining areas using UAV

    Science.gov (United States)

    Lisiecka, Ewa; Motyka, Barbara; Motyka, Zbigniew; Pierzchała, Łukasz; Szade, Adam

    2018-04-01

    The selected, remote measurement methods are discussed, useful for determining surface water properties using mobile unmanned aerial platforms (UAV). The possibilities of using this type of solutions in the scope of measuring spatial, physicochemical and biological parameters of both natural and anthropogenic water reservoirs, including flood polders, water-filled pits, settling tanks and mining sinks were analyzed. Methods of remote identification of the process of overgrowing this type of ecosystems with water and coastal plant formations have also been proposed.

  4. Specific surface area effect on adsorption of chlorpyrifos and TCP by soils and modeling

    Science.gov (United States)

    The adsorption of chlorpyrifos and TCP (3,5,6, trichloro-2-pyridinol) was determined in four soils (Mollisol, Inceptisol, Entisol, Alfisol) having different specific surface areas (19–84 m2/g) but rather similar organic matter content (2.4–3.5%). Adsorption isotherms were derived from batch equilibr...

  5. Determinants of Household Food Security in Drought Prone Areas of ...

    African Journals Online (AJOL)

    This paper documents the determinants of household-level food security based on the data collected in 2003 from 954 randomly-selected households in major drought-prone areas of Ethiopia; namely from the West and East Haraghe zones of Oromiya and South Gonder zone of Amhara. The food security is assessed using ...

  6. Regime-dependent determinants of Euro area sovereign CDS spreads

    NARCIS (Netherlands)

    Blommestein, H.J.; Eijffinger, Sylvester; Qian, Zongxin

    We study the determinants of sovereign CDS spreads of five Euro area countries (Greece, Ireland, Italy, Portugal, and Spain) after the collapse of Lehman Brothers. We find that global and/or European Monetary Union (EMU)-wide factors are the main drivers of changes in the sovereign CDS spreads in

  7. Geographical altitude, size, mass and body surface area in children (1-4 years) in the Province of Jujuy (Argentina).

    Science.gov (United States)

    Román, Estela María; Bejarano, Ignacio Felipe; Alfaro, Emma Laura; Abdo, Guadalupe; Dipierri, José Edgardo

    2015-01-01

    Highland child populations show low growth rates. To evaluate the variation of size, mass and body surface area of Jujenean infants (1-4 years) as a function of geographic altitude. Nutritional status of 8059 healthy infants was determined based on weight and height data; body mass index, ponderal index, body surface area, body surface area/mass and ectomorphy were calculated. Variables were standardized with a provincial mean and WHO references. Data were grouped by age, sex and geographic altitude: Highlands (≥2500 masl) and Lowlands (children differ in size, mass and body surface area based on the geographical altitude and adverse nutritional and socioeconomic factors.

  8. Metal-organic framework materials with ultrahigh surface areas

    Science.gov (United States)

    Farha, Omar K.; Hupp, Joseph T.; Wilmer, Christopher E.; Eryazici, Ibrahim; Snurr, Randall Q.; Gomez-Gualdron, Diego A.; Borah, Bhaskarjyoti

    2015-12-22

    A metal organic framework (MOF) material including a Brunauer-Emmett-Teller (BET) surface area greater than 7,010 m.sup.2/g. Also a metal organic framework (MOF) material including hexa-carboxylated linkers including alkyne bond. Also a metal organic framework (MOF) material including three types of cuboctahedron cages fused to provide continuous channels. Also a method of making a metal organic framework (MOF) material including saponifying hexaester precursors having alkyne bonds to form a plurality of hexa-carboxylated linkers including alkyne bonds and performing a solvothermal reaction with the plurality of hexa-carboxylated linkers and one or more metal containing compounds to form the MOF material.

  9. Asymptotic variance of grey-scale surface area estimators

    DEFF Research Database (Denmark)

    Svane, Anne Marie

    Grey-scale local algorithms have been suggested as a fast way of estimating surface area from grey-scale digital images. Their asymptotic mean has already been described. In this paper, the asymptotic behaviour of the variance is studied in isotropic and sufficiently smooth settings, resulting...... in a general asymptotic bound. For compact convex sets with nowhere vanishing Gaussian curvature, the asymptotics can be described more explicitly. As in the case of volume estimators, the variance is decomposed into a lattice sum and an oscillating term of at most the same magnitude....

  10. Polymer adsorption on platinum: surface coverage determination using iodide-125

    International Nuclear Information System (INIS)

    Ellis, T.M.; Van de Mark, M.R.; mi, FL

    1981-01-01

    Adsorption of iodide-125, a γ emitter, was used as a quantitative methodology for polymer adsorption surface coverage analysis. Adsorption of I-125 on clean platinum produced surface elemental ratios of I:Pt of 1:4. The technique was applied to the adsorption of polyethylene glycol terephthalate from trifluoroacetic acid on platinum flags with a 2-cm 2 surface area. This polymer adsorption is approximated by a logarithmic relationship similar to the Temkin isotherm. Polymer coverage attained up to 99.6% of the surface

  11. Determination of alfalfa leaf area by non-destructive method

    Directory of Open Access Journals (Sweden)

    Leonardo Bianco de Carvalho

    2011-11-01

    Full Text Available The knowledge of plant leaf area is important to evaluate the vegetal growth. The objective of this research was to determine a mathematical equation to estimate successfully alfalfa (Medicago sativa leaf area by measuring linear dimensions of the leaf blade of the plant leaflets. The leaves were collected from cultivar ‘Crioula’ cropped at field conditions in Jaboticabal, SP,Brazil. The leaflets length, width and leaf blade area were determined electronically. Linear, geometric and exponential equations were tested, considering the length and width separately and the length × width relation. The lateral leaflets showed similar dimensions and they were different to the central leaflet. So, it was opted to analyze the lateral leaflets together. All equations described satisfactorily the alfalfa leaf area, but it was opted for the linear equation passing through the origin due to its better practical application, showing high significance and normal distribution of residuals. This equation was validated with coefficient of correlation of 0.96, showing high significance (P < 0.01. The alfalfa leaf area can be estimated by the equation LA = 0,691156 × LWct + 0,3652754 × LWlt, where LWct is the central leaflet length × width and LWlt is the sum of the left and right lateral leaflets length × width.

  12. Correlating humidity-dependent ionically conductive surface area with transport phenomena in proton-exchange membranes.

    Science.gov (United States)

    He, Qinggang; Kusoglu, Ahmet; Lucas, Ivan T; Clark, Kyle; Weber, Adam Z; Kostecki, Robert

    2011-10-13

    The objective of this effort was to correlate the local surface ionic conductance of a Nafion 212 proton-exchange membrane with its bulk and interfacial transport properties as a function of water content. Both macroscopic and microscopic proton conductivities were investigated at different relative humidity levels, using direct-current voltammetry and current-sensing atomic force microscopy (CSAFM). We were able to identify small ion-conducting domains that grew with humidity at the surface of the membrane. Numerical analysis of the surface ionic conductance images recorded at various relative humidity levels helped determine the fractional area of ion-conducting active sites. A simple square-root relationship between the fractional conducting area and observed interfacial mass-transport resistance was established. Furthermore, the relationship between the bulk ionic conductivity and surface ionic conductance pattern of the Nafion membrane was examined.

  13. Correlating Humidity-Dependent Ionically Conductive Surface Area with Transport Phenomena in Proton-Exchange Membranes

    Energy Technology Data Exchange (ETDEWEB)

    He, Qinggang; Kusoglu, Ahmet; Lucas, Ivan T.; Clark, Kyle; Weber, Adam Z.; Kostecki, Robert

    2011-08-01

    The objective of this effort was to correlate the local surface ionic conductance of a Nafion? 212 proton-exchange membrane with its bulk and interfacial transport properties as a function of water content. Both macroscopic and microscopic proton conductivities were investigated at different relative humidity levels, using electrochemical impedance spectroscopy and current-sensing atomic force microscopy (CSAFM). We were able to identify small ion-conducting domains that grew with humidity at the surface of the membrane. Numerical analysis of the surface ionic conductance images recorded at various relative humidity levels helped determine the fractional area of ion-conducting active sites. A simple square-root relationship between the fractional conducting area and observed interfacial mass-transport resistance was established. Furthermore, the relationship between the bulk ionic conductivity and surface ionic conductance pattern of the Nafion? membrane was examined.

  14. Error bounds for surface area estimators based on Crofton's formula

    DEFF Research Database (Denmark)

    Kiderlen, Markus; Meschenmoser, Daniel

    2009-01-01

    According to Crofton’s formula, the surface area S(A) of a sufficiently regular compact set A in R^d is proportional to the mean of all total projections pA (u) on a linear hyperplane with normal u, uniformly averaged over all unit vectors u. In applications, pA (u) is only measured in k directio...... in the sense that the relative error of the surface area estimator is very close to the minimal error....... and the mean is approximated by a finite weighted sum S(A) of the total projections in these directions. The choice of the weights depends on the selected quadrature rule. We define an associated zonotope Z (depending only on the projection directions and the quadrature rule), and show that the relative error...... S (A)/S (A) is bounded from below by the inradius of Z and from above by the circumradius of Z. Applying a strengthened isoperimetric inequality due to Bonnesen, we show that the rectangular quadrature rule does not give the best possible error bounds for d = 2. In addition, we derive asymptotic...

  15. Biomaterial surface proteomic signature determines interaction with epithelial cells.

    Science.gov (United States)

    Abdallah, Mohamed-Nur; Tran, Simon D; Abughanam, Ghada; Laurenti, Marco; Zuanazzi, David; Mezour, Mohamed A; Xiao, Yizhi; Cerruti, Marta; Siqueira, Walter L; Tamimi, Faleh

    2017-05-01

    Cells interact with biomaterials indirectly through extracellular matrix (ECM) proteins adsorbed onto their surface. Accordingly, it could be hypothesized that the surface proteomic signature of a biomaterial might determine its interaction with cells. Here, we present a surface proteomic approach to test this hypothesis in the specific case of biomaterial-epithelial cell interactions. In particular, we determined the surface proteomic signature of different biomaterials exposed to the ECM of epithelial cells (basal lamina). We revealed that the biomaterial surface chemistry determines the surface proteomic profile, and subsequently the interaction with epithelial cells. In addition, we found that biomaterials with surface chemistries closer to that of percutaneous tissues, such as aminated PMMA and aminated PDLLA, promoted higher selective adsorption of key basal lamina proteins (laminins, nidogen-1) and subsequently improved their interactions with epithelial cells. These findings suggest that mimicking the surface chemistry of natural percutaneous tissues can improve biomaterial-epithelial integration, and thus provide a rationale for the design of improved biomaterial surfaces for skin regeneration and percutaneous medical devices. Failure of most biomaterials originates from the inability to predict and control the influence of their surface properties on biological phenomena, particularly protein adsorption, and cellular behaviour, which subsequently results in unfavourable host response. Here, we introduce a surface-proteomic screening approach using a label-free mass spectrometry technique to decipher the adsorption profile of extracellular matrix (ECM) proteins on different biomaterials, and correlate it with cellular behaviour. We demonstrated that the way a biomaterial selectively interacts with specific ECM proteins of a given tissue seems to determine the interactions between the cells of that tissue and biomaterials. Accordingly, this approach can

  16. Variability of silver fir (Abies alba Mill. cones – variability structure of scale surface area

    Directory of Open Access Journals (Sweden)

    Aniszewska Monika

    2017-03-01

    Full Text Available This study was conducted on a batch of closed silver fir cones from Jawor Forest District and a mixture of scales from the seed extraction facility Grotniki. The scales were divided into three size classes corresponding to the bottom, middle and upper part of the cones and their area was measured with the Multi Scan Base v.18.03 software. Based on the sum of the inner and outer surface area of all scales, we then determined the total area of evaporation from the cones. In addition, the area of protruding scales was measured for differently sized scales from different parts of the cones. Previous studies have shown that the average outer surface of a closed cone, calculated as the sum of protruding scales, accounts for 10% of the outer surface of an open cone. Pictures of both scale surfaces with the internal seed bed and the external protrusions were taken using a scanning electron microscope. We noticed significant differences in dimension and shape of the channels and trichomes on the scale surface. On the inner side of the scales, we found a high diversity of trichomes of different lengths, whilst the outer side contained channels. Presumably, these characteristics affect the rate of water loss from the cones during desiccation and separation of the seed. In-depth knowledge on the evaporative surfaces of fir cones and scale structure will be helpful for optimizing the industrial processes of seed extraction.

  17. Evaluating polymer degradation with complex mixtures using a simplified surface area method.

    Science.gov (United States)

    Steele, Kandace M; Pelham, Todd; Phalen, Robert N

    2017-09-01

    Chemical-resistant gloves, designed to protect workers from chemical hazards, are made from a variety of polymer materials such as plastic, rubber, and synthetic rubber. One material does not provide protection against all chemicals, thus proper polymer selection is critical. Standardized testing, such as chemical degradation tests, are used to aid in the selection process. The current methods of degradation ratings based on changes in weight or tensile properties can be expensive and data often do not exist for complex chemical mixtures. There are hundreds of thousands of chemical products on the market that do not have chemical resistance data for polymer selection. The method described in this study provides an inexpensive alternative to gravimetric analysis. This method uses surface area change to evaluate degradation of a polymer material. Degradation tests for 5 polymer types against 50 complex mixtures were conducted using both gravimetric and surface area methods. The percent change data were compared between the two methods. The resulting regression line was y = 0.48x + 0.019, in units of percent, and the Pearson correlation coefficient was r = 0.9537 (p ≤ 0.05), which indicated a strong correlation between percent weight change and percent surface area change. On average, the percent change for surface area was about half that of the weight change. Using this information, an equivalent rating system was developed for determining the chemical degradation of polymer gloves using surface area.

  18. Groundwater Quality Assessment for Waste Management Area U: First Determination

    Energy Technology Data Exchange (ETDEWEB)

    Hodges, Floyd N.; Chou, Charissa J.

    2000-08-04

    As a result of the most recent recalculation one of the indicator parameters, specific conductance, exceeded its background value in downgradient well 299-W19-41, triggering a change from detection monitoring to groundwater quality assessment program. The major contributors to the higher specific conductance are nonhazardous constituents (i.e., sodium, calcium, magnesium, chloride, sulfate, and bicarbonate). Nitrate, chromium, and technetium-99 are present and are increasing; however, they are significantly below their drinking waster standards. Interpretation of groundwater monitoring data indicates that both the nonhazardous constituents causing elevated specific conductance in groundwater and the tank waste constituents present in groundwater at the waste management area are a result of surface water infiltration in the southern portion of the facility. There is evidence for both upgradient and waste management area sources for observed nitrate concentrations. There is no indication of an upgradient source for the observed chromium and technetium-99.

  19. Predictive analysis effectiveness in determining the epidemic disease infected area

    Science.gov (United States)

    Ibrahim, Najihah; Akhir, Nur Shazwani Md.; Hassan, Fadratul Hafinaz

    2017-10-01

    Epidemic disease outbreak had caused nowadays community to raise their great concern over the infectious disease controlling, preventing and handling methods to diminish the disease dissemination percentage and infected area. Backpropagation method was used for the counter measure and prediction analysis of the epidemic disease. The predictive analysis based on the backpropagation method can be determine via machine learning process that promotes the artificial intelligent in pattern recognition, statistics and features selection. This computational learning process will be integrated with data mining by measuring the score output as the classifier to the given set of input features through classification technique. The classification technique is the features selection of the disease dissemination factors that likely have strong interconnection between each other in causing infectious disease outbreaks. The predictive analysis of epidemic disease in determining the infected area was introduced in this preliminary study by using the backpropagation method in observation of other's findings. This study will classify the epidemic disease dissemination factors as the features for weight adjustment on the prediction of epidemic disease outbreaks. Through this preliminary study, the predictive analysis is proven to be effective method in determining the epidemic disease infected area by minimizing the error value through the features classification.

  20. Tritium in Precipitation, Surface and Groundwaters in the Zagreb Area

    International Nuclear Information System (INIS)

    Horvatincic, N.; Baresic, J.; Sironic, A.; Krajcar Bronic, I.; Obelic, B.

    2011-01-01

    Radioactive isotope tritium (3H) and stable isotopes of hydrogen (2H/1H) and oxygen (18O/16O) were measured in Sava River, precipitation and groundwater at 3 monitoring wells (piezometers) and 1 production well of the Petrusevec aquifer, close to the Sava River. Samples were collected monthly during 2010. The investigation is included in the Regional IAEA Project RER/8/016 Using Environmental Isotopes for Evaluation of Streamwater/Groundwater Interactions in Selected Aquifers in the Danube Basin. Sava River is a tributary of Danube River and the aim of the investigation is to determine the influence of surface stream of Sava River to the groundwater of aquifer used for water exploitation. In this work only 3H results were presented. 3H was measured by liquid scintillation counter Quantulus 1220, using electrolytic enrichment for all samples. 3H activity in precipitation showed slight seasonal fluctuation between 4 TU and 14 TU, with higher values in summer. 3H activity of Sava River and groundwater of the Petrusevec aquifer followed 3H of precipitation till May 2010. Significant increase of 3H in Sava River was observed in June, (199 @ 20) TU, and in the next month it fell down at 6 TU. Increase of 3H was also observed in groundwater but with damped response (maximum 60 TU) and with delay of 2 - 3 months related to Sava River. Different response of different piezometers and the well indicated the different infiltration times of surface water of Sava River to groundwater of the Petrusevec aquifer. The increased 3H activity in surface and groundwaters was caused by release of tritiated water from the Krsko Nuclear Power Plant, 30 km upstream from Zagreb. The results of 3H, 2H/1H and 18O/16O measurements will be used to determine the infiltration time of groundwater of the Petrusevec aquifer using conceptual and mathematical models. (author)

  1. Voltammetric determination of metal impurities on semiconductor surface

    International Nuclear Information System (INIS)

    Knyazeva, E.P.; Mokrousov, G.M.; Volkova, V.N.

    1995-01-01

    A modification of voltamperometric method used for analysis of semiconductor surfaces which make it possible to exclude a contact between surface and background solution. This technique is based on solubility of elemental metal forms in low melting electroconductor systems (e.g., in mercury. The voltampere characteristics of amalgams formed are then studied. The suggested method is simple, rapid, and makes it possible to perform a nondestructive qualitative analysis of the sample surface area measuring about 10 -3 cm -2 and more. 4 refs.; 2 figs

  2. Urban Surface Radiative Energy Budgets Determined Using Aircraft Scanner Data

    Science.gov (United States)

    Luvall, Jeffrey C.; Quattrochi, Dale A.; Rickman, Doug L.; Estes, Maury G.; Arnold, James E. (Technical Monitor)

    2002-01-01

    It is estimated that by the year 2025, 80% of the world's population will live in cities. The extent of these urban areas across the world can be seen in an image of city lights from the Defense Meteorological Satellite Program. In many areas of North America and Europe, it is difficult to separate individual cities because of the dramatic growth and sprawl of urbanized areas. This conversion of the natural landscape vegetation into man-made urban structures such as roads and buildings drastically alter the regional surface energy budgets, hydrology, precipitation patterns, and meteorology. One of the earliest recognized and measured phenomena of urbanization is the urban heat island (UHI) which was reported as early as 1833 for London and 1862 for Paris. The urban heat island results from the energy that is absorbed by man-made materials during the day and is released at night resulting in the heating of the air within the urban area. The magnitude of the air temperature difference between the urban and surrounding countryside is highly dependent on the structure of the urban area, amount of solar immolation received during the day, and atmospheric conditions during the night. These night time air temperature differences can be in the range of 2 to 5 C. or greater. Although day time air temperature differences between urban areas and the countryside exists during the day, atmospheric mixing and stability reduce the magnitude. This phenomena is not limited to large urban areas, but also occurs in smaller metropolitan areas. The UHI has significant impacts on the urban air quality, meteorology, energy use, and human health. The UPI can be mitigated through increasing the amount of vegetation and modification of urban surfaces using high albedo materials for roofs and paved surfaces. To understand why the urban heat island phenomenon exists it is useful to define the surface in terms of the surface energy budget. Surface temperature and albedo is a major component of

  3. Method for producing high surface area chromia materials for catalysis

    Science.gov (United States)

    Gash, Alexander E [Brentwood, CA; Satcher, Joe [Patterson, CA; Tillotson, Thomas [Tracy, CA; Hrubesh, Lawrence [Pleasanton, CA; Simpson, Randall [Livermore, CA

    2007-05-01

    Nanostructured chromium(III)-oxide-based materials using sol-gel processing and a synthetic route for producing such materials are disclosed herein. Monolithic aerogels and xerogels having surface areas between 150 m.sup.2/g and 520 m.sup.2/g have been produced. The synthetic method employs the use of stable and inexpensive hydrated-chromium(III) inorganic salts and common solvents such as water, ethanol, methanol, 1-propanol, t-butanol, 2-ethoxy ethanol, and ethylene glycol, DMSO, and dimethyl formamide. The synthesis involves the dissolution of the metal salt in a solvent followed by an addition of a proton scavenger, such as an epoxide, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively.

  4. Fully automated algorithm for wound surface area assessment.

    Science.gov (United States)

    Deana, Alessandro Melo; de Jesus, Sérgio Henrique Costa; Sampaio, Brunna Pileggi Azevedo; Oliveira, Marcelo Tavares; Silva, Daniela Fátima Teixeira; França, Cristiane Miranda

    2013-01-01

    Worldwide, clinicians, dentists, nurses, researchers, and other health professionals need to monitor the wound healing progress and to quantify the rate of wound closure. The aim of this study is to demonstrate, step by step, a fully automated numerical method to estimate the size of the wound and the percentage damaged relative to the body surface area (BSA) in images, without the requirement for human intervention. We included the formula for BSA in rats in the algorithm. The methodology was validated in experimental wounds and human ulcers and was compared with the analysis of an experienced pathologist, with good agreement. Therefore, this algorithm is suitable for experimental wounds and burns and human ulcers, as they have a high contrast with adjacent normal skin. © 2013 by the Wound Healing Society.

  5. Electromagnetic surface waves for large-area RF plasma productions between large-area planar electrodes

    International Nuclear Information System (INIS)

    Nonaka, S.

    1992-01-01

    Recently, large-area plasma production has been tested by means of a 13.56 MHz radio-frequency (RF) discharge between a pair of large-area planar electrodes, approximately 0.5 m x 1.4 m, as one of the semiconductor technologies for fabrication of large-area amorphous silicon solar cells in the ''Sunshine Project'' of the Agency of Industrial Science and Technology in Japan. We also confirmed long plasma production between a pair of long electrodes. In this paper, normal electromagnetic (EM) waves propagating in a region between a planar waveguide with one plasma and two dielectric layers are analyzed in order to study the feasibility of large-area plasma productions by EM wave-discharges between a pair of large-area RF electrodes larger than the half-wavelength of RF wave. In conclusion, plasmas higher than an electron plasma frequency will be produced by an odd TMoo surface mode. (author) 4 refs., 3 figs

  6. Human cortical areas involved in perception of surface glossiness.

    Science.gov (United States)

    Wada, Atsushi; Sakano, Yuichi; Ando, Hiroshi

    2014-09-01

    Glossiness is the visual appearance of an object's surface as defined by its surface reflectance properties. Despite its ecological importance, little is known about the neural substrates underlying its perception. In this study, we performed the first human neuroimaging experiments that directly investigated where the processing of glossiness resides in the visual cortex. First, we investigated the cortical regions that were more activated by observing high glossiness compared with low glossiness, where the effects of simple luminance and luminance contrast were dissociated by controlling the illumination conditions (Experiment 1). As cortical regions that may be related to the processing of glossiness, V2, V3, hV4, VO-1, VO-2, collateral sulcus (CoS), LO-1, and V3A/B were identified, which also showed significant correlation with the perceived level of glossiness. This result is consistent with the recent monkey studies that identified selective neural response to glossiness in the ventral visual pathway, except for V3A/B in the dorsal visual pathway, whose involvement in the processing of glossiness could be specific to the human visual system. Second, we investigated the cortical regions that were modulated by selective attention to glossiness (Experiment 2). The visual areas that showed higher activation to attention to glossiness than that to either form or orientation were identified as right hV4, right VO-2, and right V3A/B, which were commonly identified in Experiment 1. The results indicate that these commonly identified visual areas in the human visual cortex may play important roles in glossiness perception. Copyright © 2014. Published by Elsevier Inc.

  7. Assessment of Surface Area Characteristics of Dental Implants with Gradual Bioactive Surface Treatment

    Science.gov (United States)

    Czan, Andrej; Babík, Ondrej; Miklos, Matej; Záušková, Lucia; Mezencevová, Viktória

    2017-10-01

    Since most of the implant surface is in direct contact with bone tissue, shape and integrity of said surface has great influence on successful osseointegration. Among other characteristics that predetermine titanium of different grades of pureness as ideal biomaterial, titanium shows high mechanical strength making precise miniature machining increasingly difficult. Current titanium-based implants are often anodized due to colour coding. This anodized layer has important functional properties for right usage and also bio-compatibility of dental implants. Physical method of anodizing and usage of anodizing mediums has a significant influence on the surface quality and itself functionality. However, basic requirement of the dental implant with satisfactory properties is quality of machined surface before anodizing. Roughness, for example, is factor affecting of time length of anodizing operation and so whole productivity. The paper is focused on monitoring of surface and area characteristics, such as roughness or surface integrity after different cutting conditions of miniature machining of dental implants and their impact on suitability for creation of satisfactory anodized layer with the correct biocompatible functional properties.

  8. Surface ozone in the urban area of Manaus, Amazonas, Brazil

    Science.gov (United States)

    Souza, R. A. F. D.; Costa, P. S.; Silva, C.; Godoi, R. M.; Martin, S. T.; Tota, J.; Barbosa, H. M.; Pauliquevis, T.; Ferreira De Brito, J.; Artaxo, P.; Manzi, A. O.; Wolf, S. A.; Cirino, G. G.

    2014-12-01

    When nitrogen oxides from vehicle and industrial emissions mix with volatile organic compounds from trees and plants with exposure to sunlight, a chemical reaction occurs contributing to ground-level ozone pollution. The preliminary results of the surface ozone study in urban area of Manaus, Amazonas State, Brazil, are presented for the first intensive operating period (IOP1) of the GoAmazon experiment (February/March 2014). Photochemical ozone production was found to be a regular process, with an afternoon maximum of the ozone mixing ratio of lower than 20 ppbv for cloudy days or clear sky weather. Typical ozone concentrations at mid-day were low (about 10 ppb). On the other hand, several high-value ozone episodes with surface ozone mixing ratios up to three times larger were registered during the dry season of 2013 (September/October). At the beginning of the wet season, the ozone concentration in Manaus decreased significantly, but diurnal variations can be found during the days with rainfall and other fast changes of meteorological conditions. Possible explanations of the nature of pulsations are discussed. Photochemical ozone production by local urban plumes of Manaus is named as a first possible source of the ozone concentration and biomass burning or power plant emissions are suggested as an alternative or an additional source.

  9. Estimating the surface area of birds: using the homing pigeon (Columba livia as a model

    Directory of Open Access Journals (Sweden)

    Cristina R. Perez

    2014-05-01

    Full Text Available Estimation of the surface area of the avian body is valuable for thermoregulation and metabolism studies as well as for assessing exposure to oil and other surface-active organic pollutants from a spill. The use of frozen carcasses for surface area estimations prevents the ability to modify the posture of the bird. The surface area of six live homing pigeons in the fully extended flight position was estimated using a noninvasive method. An equation was derived to estimate the total surface area of a pigeon based on its body weight. A pigeon's surface area in the fully extended flight position is approximately 4 times larger than the surface area of a pigeon in the perching position. The surface area of a bird is dependent on its physical position, and, therefore, the fully extended flight position exhibits the maximum area of a bird and should be considered the true surface area of a bird.

  10. Determining management strategies for the Sarikum Nature Protection Area.

    Science.gov (United States)

    Öztürk, Sevgi

    2015-03-01

    In recent years, many environmental problems have become important factors in promoting the economic need to develop tourist activity: climate change such as energy wars, increasing hunger and aridity, population increases in urban areas, excessive and unthinking use of natural resources, difficult international relations, economic competition, and increasing environmental stress. Trends in global tourism have changed with changes in culture and our attitude to nature. Changes in both the profile and consumption patterns of tourists have called for the need to balance the use of natural and cultural assets with the need to adequately protect them. In this study, the Sarikum Nature Protection Area (SNPA) was selected as a case study because of its significance as a Turkish wetland area and the variety of different ecosystems coexisting within it. The study focussed on management strategies, but also provides a broader strategy for an area that currently has no management plan. Strengths and weaknesses, opportunities and threats (SWOT) analyses of the area were gathered and analyzed using R'WOT analysis (ranking + SWOT), a multi-criteria assessment method, in order to determine strategies, obtain the participation of interest groups, and assess their opinions and attitudes. The analysis showed the following: the rich biological diversity and the existence of endemic species were the reserve's most significant strength; the presence of natural areas in surrounding regions was the most significant opportunity; the shortage of infrastructure and lack of legal regulation of ecotourism was the most significant weakness; and the lack of a management plan was the most immediate threat.

  11. NEW CONCEPTS AND TEST METHODS OF CURVE PROFILE AREA DENSITY IN SURFACE: ESTIMATION OF AREAL DENSITY ON CURVED SPATIAL SURFACE

    OpenAIRE

    Hong Shen

    2011-01-01

    The concepts of curve profile, curve intercept, curve intercept density, curve profile area density, intersection density in containing intersection (or intersection density relied on intersection reference), curve profile intersection density in surface (or curve intercept intersection density relied on intersection of containing curve), and curve profile area density in surface (AS) were defined. AS expressed the amount of curve profile area of Y phase in the unit containing surface area, S...

  12. Moving to 3D: relationships between coral planar area, surface area and volume.

    Science.gov (United States)

    House, Jenny E; Brambilla, Viviana; Bidaut, Luc M; Christie, Alec P; Pizarro, Oscar; Madin, Joshua S; Dornelas, Maria

    2018-01-01

    Coral reefs are a valuable and vulnerable marine ecosystem. The structure of coral reefs influences their health and ability to fulfill ecosystem functions and services. However, monitoring reef corals largely relies on 1D or 2D estimates of coral cover and abundance that overlook change in ecologically significant aspects of the reefs because they do not incorporate vertical or volumetric information. This study explores the relationship between 2D and 3D metrics of coral size. We show that surface area and volume scale consistently with planar area, albeit with morphotype specific conversion parameters. We use a photogrammetric approach using open-source software to estimate the ability of photogrammetry to provide measurement estimates of corals in 3D. Technological developments have made photogrammetry a valid and practical technique for studying coral reefs. We anticipate that these techniques for moving coral research from 2D into 3D will facilitate answering ecological questions by incorporating the 3rd dimension into monitoring.

  13. Spectroscopic determination of optimal hydration time of zircon surface

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez R, E. [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Garcia R, G. [Instituto Tecnologico de Toluca, Division de Estudios del Posgrado, Av. Tecnologico s/n, Ex-Rancho La Virgen, 52140 Metepec, Estado de Mexico (Mexico); Garcia G, N., E-mail: eduardo.ordonez@inin.gob.m [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Av. Colon y Av. Tollocan, 50180 Toluca, Estado de Mexico (Mexico)

    2010-07-01

    When a mineral surface is immersed in an aqueous solution, it develops and electric charge produced by the amphoteric dissociation of hydroxyl groups created by the hydration of the solid surface. This is one influential surface property. The complete hydration process takes a time which is specific for each mineral species. The knowledge of the aqueous solution contact time for complete surface hydration is mandatory for further surface phenomena studies. This study deals with the optimal hydration time of the raw zircon (ZrSiO{sub 4}) surface comparing the classical potentiometric titrations with a fluorescence spectroscopy technique. The latter is easy and rea liable as it demands only one sample batch to determine the optimal time to ensure a total hydration of the zircon surface. The analytical results of neutron activation analysis showed the presence of trace quantities of Dy{sup 3+}, Eu{sup 3+} and Er{sup 3} in the bulk of zircon. The Dy{sup 3+} is structured in the zircon crystalline lattice and undergoes the same chemical reactions as zircon. Furthermore, the Dy{sup 3+} has a good fluorescent response whose intensity is enhanced by hydration molecules. The results show that, according to the potentiometric analysis, the hydration process for each batch (at least 8 sample batches) takes around 2 h, while the spectrometric method indicates only 5 minutes from only one batch. Both methods showed that the zircon surface have a 16 h optimal hydration time. (Author)

  14. Spectroscopic determination of optimal hydration time of zircon surface

    International Nuclear Information System (INIS)

    Ordonez R, E.; Garcia R, G.; Garcia G, N.

    2010-01-01

    When a mineral surface is immersed in an aqueous solution, it develops and electric charge produced by the amphoteric dissociation of hydroxyl groups created by the hydration of the solid surface. This is one influential surface property. The complete hydration process takes a time which is specific for each mineral species. The knowledge of the aqueous solution contact time for complete surface hydration is mandatory for further surface phenomena studies. This study deals with the optimal hydration time of the raw zircon (ZrSiO 4 ) surface comparing the classical potentiometric titrations with a fluorescence spectroscopy technique. The latter is easy and rea liable as it demands only one sample batch to determine the optimal time to ensure a total hydration of the zircon surface. The analytical results of neutron activation analysis showed the presence of trace quantities of Dy 3+ , Eu 3+ and Er 3 in the bulk of zircon. The Dy 3+ is structured in the zircon crystalline lattice and undergoes the same chemical reactions as zircon. Furthermore, the Dy 3+ has a good fluorescent response whose intensity is enhanced by hydration molecules. The results show that, according to the potentiometric analysis, the hydration process for each batch (at least 8 sample batches) takes around 2 h, while the spectrometric method indicates only 5 minutes from only one batch. Both methods showed that the zircon surface have a 16 h optimal hydration time. (Author)

  15. Surface temperature and surface heat flux determination of the inverse heat conduction problem for a slab

    International Nuclear Information System (INIS)

    Kuroyanagi, Toshiyuki

    1983-07-01

    Based on an idea that surface conditions should be a reflection of interior temperature and interior heat flux variation as inverse as interior conditions has been determined completely by the surface temperature and/on surface heat flux as boundary conditions, a method is presented for determining the surface temperature and the surface heat flux of a solid when the temperature and heat flux at an interior point are a prescribed function of time. The method is developed by the integration of Duhumels' integral which has unknown temperature or unknown heat flux in its integrand. Specific forms of surface condition determination are developed for a sample inverse problem: slab. Ducussing the effect of a degree of avairable informations at an interior point due to damped system and the effect of variation of surface conditions on those formulations, it is shown that those formulations are capable of representing the unknown surface conditions except for small time interval followed by discontinuous change of surface conditions. The small un-resolved time interval is demonstrated by a numerical example. An evaluation method of heat flux at an interior point, which is requested by those formulations, is discussed. (author)

  16. Ambient pressure dried tetrapropoxysilane-based silica aerogels with high specific surface area

    Science.gov (United States)

    Parale, Vinayak G.; Han, Wooje; Jung, Hae-Noo-Ree; Lee, Kyu-Yeon; Park, Hyung-Ho

    2018-01-01

    In the present paper, we report the synthesis of tetrapropoxysilane (TPOS)-based silica aerogels with high surface area and large pore volume. The silica aerogels were prepared by a two-step sol-gel process followed by surface modification via a simple ambient pressure drying approach. In order to minimize drying shrinkage and obtain hydrophobic aerogels, the surface of the alcogels was modified using trichloromethylsilane as a silylating agent. The effect of the sol-gel compositional parameters on the polymerization of aerogels prepared by TPOS, one of the precursors belonging to the Si(OR)4 family, was reported for the first time. The oxalic acid and NH4OH concentrations were adjusted to achieve good-quality aerogels with high surface area, low density, and high transparency. Controlling the hydrolysis and condensation reactions of the TPOS precursor turned out to be the most important factor to determine the pore characteristics of the aerogel. Highly transparent aerogels with high specific surface area (938 m2/g) and low density (0.047 g/cm3) could be obtained using an optimized TPOS/MeOH molar ratio with appropriate concentrations of oxalic acid and NH4OH.

  17. Minimal area surfaces dual to Wilson loops and the Mathieu equation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Changyu; He, Yifei; Kruczenski, Martin [Department of Physics and Astronomy, Purdue University, 525 Northwestern Avenue, W. Lafayette, IN, 47907-2036 (United States)

    2016-08-11

    The AdS/CFT correspondence relates Wilson loops in N=4 SYM to minimal area surfaces in AdS{sub 5}×S{sup 5} space. Recently, a new approach to study minimal area surfaces in AdS{sub 3}⊂AdS{sub 5} was discussed based on a Schroedinger equation with a periodic potential determined by the Schwarzian derivative of the shape of the Wilson loop. Here we use the Mathieu equation, a standard example of a periodic potential, to obtain a class of Wilson loops such that the area of the dual minimal area surface can be computed analytically in terms of eigenvalues of such equation. As opposed to previous examples, these minimal surfaces have an umbilical point (where the principal curvatures are equal) and are invariant under λ-deformations. In various limits they reduce to the single and multiple wound circular Wilson loop and to the regular light-like polygons studied by Alday and Maldacena. In this last limit, the periodic potential becomes a series of deep wells each related to a light-like segment. Small corrections are described by a tight-binding approximation. In the circular limit they are well approximated by an expansion developed by A. Dekel. In the particular case of no umbilical points they reduce to a previous solution proposed by J. Toledo. The construction works both in Euclidean and Minkowski signature of AdS{sub 3}.

  18. Minimal area surfaces dual to Wilson loops and the Mathieu equation

    Science.gov (United States)

    Huang, Changyu; He, Yifei; Kruczenski, Martin

    2016-08-01

    The AdS/CFT correspondence relates Wilson loops in {N}=4 SYM to minimal area surfaces in AdS 5 × S 5 space. Recently, a new approach to study minimal area surfaces in AdS 3 ⊂ AdS 5 was discussed based on a Schroedinger equation with a periodic potential determined by the Schwarzian derivative of the shape of the Wilson loop. Here we use the Mathieu equation, a standard example of a periodic potential, to obtain a class of Wilson loops such that the area of the dual minimal area surface can be computed analytically in terms of eigenvalues of such equation. As opposed to previous examples, these minimal surfaces have an umbilical point (where the principal curvatures are equal) and are invariant under λ-deformations. In various limits they reduce to the single and multiple wound circular Wilson loop and to the regular light-like polygons studied by Alday and Maldacena. In this last limit, the periodic potential becomes a series of deep wells each related to a light-like segment. Small corrections are described by a tight-binding approximation. In the circular limit they are well approximated by an expansion developed by A. Dekel. In the particular case of no umbilical points they reduce to a previous solution proposed by J. Toledo. The construction works both in Euclidean and Minkowski signature of AdS 3.

  19. Strong and tough cellulose nanopaper with high specific surface area and porosity.

    Science.gov (United States)

    Sehaqui, Houssine; Zhou, Qi; Ikkala, Olli; Berglund, Lars A

    2011-10-10

    In order to better understand nanostructured fiber networks, effects from high specific surface area of nanofibers are important to explore. For cellulose networks, this has so far only been achieved in nonfibrous regenerated cellulose aerogels. Here, nanofibrillated cellulose (NFC) is used to prepare high surface area nanopaper structures, and the mechanical properties are measured in tensile tests. The water in NFC hydrogels is exchanged to liquid CO2, supercritical CO2, and tert-butanol, followed by evaporation, supercritical drying, and sublimation, respectively. The porosity range is 40-86%. The nanofiber network structure in nanopaper is characterized by FE-SEM and nitrogen adsorption, and specific surface area is determined. High-porosity TEMPO-oxidized NFC nanopaper (56% porosity) prepared by critical point drying has a specific surface area as high as 482 m(2) g(-1). The mechanical properties of this nanopaper structure are better than for many thermoplastics, but at a significantly lower density of only 640 kg m(-3). The modulus is 1.4 GPa, tensile strength 84 MPa, and strain-to-failure 17%. Compared with water-dried nanopaper, the material is softer with substantiallly different deformation behavior.

  20. Escaping the correction for body surface area when calculating glomerular filtration rate in children

    Energy Technology Data Exchange (ETDEWEB)

    Piepsz, Amy; Tondeur, Marianne [CHU St. Pierre, Department of Radioisotopes, Brussels (Belgium); Ham, Hamphrey [University Hospital Ghent, Department of Nuclear Medicine, Ghent (Belgium)

    2008-09-15

    {sup 51}Cr ethylene diamine tetraacetic acid ({sup 51}Cr EDTA) clearance is nowadays considered as an accurate and reproducible method for measuring glomerular filtration rate (GFR) in children. Normal values in function of age, corrected for body surface area, have been recently updated. However, much criticism has been expressed about the validity of body surface area correction. The aim of the present paper was to present the normal GFR values, not corrected for body surface area, with the associated percentile curves. For that purpose, the same patients as in the previous paper were selected, namely those with no recent urinary tract infection, having a normal left to right {sup 99m}Tc MAG3 uptake ratio and a normal kidney morphology on the early parenchymal images. A single blood sample method was used for {sup 51}Cr EDTA clearance measurement. Clearance values, not corrected for body surface area, increased progressively up to the adolescence. The percentile curves were determined and allow, for a single patient, to estimate accurately the level of non-corrected clearance and the evolution with time, whatever the age. (orig.)

  1. Extent of Stream Burial and Relationships to Watershed Area, Topography, and Impervious Surface Area

    Directory of Open Access Journals (Sweden)

    Roy E. Weitzell

    2016-11-01

    Full Text Available Stream burial—the routing of streams through culverts, pipes, and concrete lined channels, or simply paving them over—is common during urbanization, and disproportionately affects small, headwater streams. Burial undermines the physical and chemical processes governing life in streams, with consequences for water quality and quantity that may amplify from headwaters to downstream receiving waters. Knowledge of the extent of stream burial is critical for understanding cumulative impacts to stream networks, and for future decision-making allowing for urban development while protecting ecosystem function. We predicted stream burial across the urbanizing Potomac River Basin (USA for each 10-m stream segment in the basin from medium-resolution impervious cover data and training observations obtained from high-resolution aerial photography in a GIS. Results were analyzed across a range in spatial aggregation, including counties and independent cities, small watersheds, and regular spatial grids. Stream burial was generally correlated with total impervious surface area (ISA, with areas exhibiting ISA above 30% often subject to elevated ratios of stream burial. Recurring patterns in burial predictions related to catchment area and topographic slope were also detected. We discuss these results in the context of physiographic constraints on stream location and urban development, including implications for environmental management of aquatic resources.

  2. Determination of Surface Fluxes Using a Bowen Ratio System

    African Journals Online (AJOL)

    USER

    Abstract. Components of the surface fluxes of the energy balance equation were determined using a Campbell Bowen ratio system. The fluxes are obtained by the energy balance Bowen ratio technique, a gradient method that uses vertical gradients of temperature and vapour pressure in combination with point ...

  3. Climatologies at high resolution for the earth's land surface areas

    Science.gov (United States)

    Karger, Dirk Nikolaus; Conrad, Olaf; Böhner, Jürgen; Kawohl, Tobias; Kreft, Holger; Soria-Auza, Rodrigo Wilber; Zimmermann, Niklaus E.; Linder, H. Peter; Kessler, Michael

    2017-09-01

    High-resolution information on climatic conditions is essential to many applications in environmental and ecological sciences. Here we present the CHELSA (Climatologies at high resolution for the earth's land surface areas) data of downscaled model output temperature and precipitation estimates of the ERA-Interim climatic reanalysis to a high resolution of 30 arc sec. The temperature algorithm is based on statistical downscaling of atmospheric temperatures. The precipitation algorithm incorporates orographic predictors including wind fields, valley exposition, and boundary layer height, with a subsequent bias correction. The resulting data consist of a monthly temperature and precipitation climatology for the years 1979-2013. We compare the data derived from the CHELSA algorithm with other standard gridded products and station data from the Global Historical Climate Network. We compare the performance of the new climatologies in species distribution modelling and show that we can increase the accuracy of species range predictions. We further show that CHELSA climatological data has a similar accuracy as other products for temperature, but that its predictions of precipitation patterns are better.

  4. Surface Rupture Effects on Earthquake Moment-Area Scaling Relations

    Science.gov (United States)

    Luo, Yingdi; Ampuero, Jean-Paul; Miyakoshi, Ken; Irikura, Kojiro

    2017-09-01

    Empirical earthquake scaling relations play a central role in fundamental studies of earthquake physics and in current practice of earthquake hazard assessment, and are being refined by advances in earthquake source analysis. A scaling relation between seismic moment ( M 0) and rupture area ( A) currently in use for ground motion prediction in Japan features a transition regime of the form M 0- A 2, between the well-recognized small (self-similar) and very large (W-model) earthquake regimes, which has counter-intuitive attributes and uncertain theoretical underpinnings. Here, we investigate the mechanical origin of this transition regime via earthquake cycle simulations, analytical dislocation models and numerical crack models on strike-slip faults. We find that, even if stress drop is assumed constant, the properties of the transition regime are controlled by surface rupture effects, comprising an effective rupture elongation along-dip due to a mirror effect and systematic changes of the shape factor relating slip to stress drop. Based on this physical insight, we propose a simplified formula to account for these effects in M 0- A scaling relations for strike-slip earthquakes.

  5. Standard Test Method for Gravimetric Determination of Nonvolatile Residue (NVR) in Environmentally Controlled Areas for Spacecraft

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method covers the determination of nonvolatile residue (NVR) fallout in environmentally controlled areas used for the assembly, testing, and processing of spacecraft. 1.2 The NVR of interest is that which is deposited on sampling plate surfaces at room temperature: it is left to the user to infer the relationship between the NVR found on the sampling plate surface and that found on any other surfaces. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

  6. 30 CFR 912.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 912.764 Section 912.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE IDAHO § 912.764 Process for designating areas unsuitable for surface coal mining... coal mining and reclamation operations. ...

  7. Relationship between the Physical Properties and Surface Area of Cellulose Derived from Adsorbates of Various Molecular Sizes.

    Science.gov (United States)

    Ougiya, H; Hioki, N; Watanabe, K; Morinaga, Y; Yoshinaga, F; Samejima, M

    1998-01-01

    An aqueous suspension of bacterial cellulose (BC) has such physical properties as higher viscosity, emulsion-stabilizing effect and filler retention than cellulose of other origins. The specific surface areas of BC, microfibrillated cellulose and wood pulp were evaluated by determining the maximum amounts of adsorption of Congo red, cellobiose dehydrogenase (CDH) and xyloglucan. There was a positive linear correlation between the above-mentioned physical properties of each cellulose sample and the specific surface area derived from the maximum amount of CDH adsorbed. The highest physical property values for BC result from the largest external surface area of the fibrils of BC to which CDH was adsorbed.

  8. 30 CFR 941.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE SOUTH DAKOTA § 941.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  9. 30 CFR 937.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE OREGON § 937.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining and... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  10. 30 CFR 905.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE CALIFORNIA § 905.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  11. 30 CFR 910.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE GEORGIA § 910.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  12. 30 CFR 903.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE ARIZONA § 903.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, applies to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  13. 30 CFR 939.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE RHODE ISLAND § 939.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  14. 30 CFR 922.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE MICHIGAN § 922.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  15. 30 CFR 921.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE MASSACHUSETTS § 921.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  16. 30 CFR 912.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE IDAHO § 912.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining and... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  17. 30 CFR 947.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE WASHINGTON § 947.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  18. 30 CFR 942.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE TENNESSEE § 942.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  19. 30 CFR 903.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 903.762 Section 903.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE ARIZONA § 903.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  20. 30 CFR 922.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 922.762 Section 922.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE MICHIGAN § 922.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  1. 30 CFR 937.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 937.762 Section 937.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE OREGON § 937.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  2. 30 CFR 912.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 912.762 Section 912.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE IDAHO § 912.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  3. 30 CFR 910.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 910.762 Section 910.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE GEORGIA § 910.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  4. The simple method of determination peaks areas in multiplets

    International Nuclear Information System (INIS)

    Loska, L.; Ptasinski, J.

    1991-01-01

    Semiconductor germanium detectors used in γ-spectrometry give spectra with well-separated peaks. However, in some cases, energies of γ-lines are too near, to produce resolved and undisturbed peaks. Then, there is a necessity to perform a mathematical separation. The method proposed here is based on the assumption, that areas of peaks composing the analysed multiplet are proportional to their heights. The method can be applied for any number of interfering peaks, providing, that the function of the background under the multiplet is accurately determined. The results of testing calculations performed on a simulated spectrum are given. The method works successfully in a computer program used for neutron activation analysis data processing. (author). 9 refs, 1 fig, 1 tab

  5. Electrochemical determination of the onset of bacterial surface adhesion

    Science.gov (United States)

    Jones, Akhenaton-Andrew; Buie, Cullen

    2017-11-01

    Microbial biofouling causes economic loss through corrosion and drag losses on ship hulls, and in oil and food distribution. Microorganisms interacting with surfaces under these open channel flows contend with high shear rates and active transport to the surface. The metallic surfaces they interact with carry charge at various potentials that are little addressed in literature. In this study we demonstrate that the Levich curve, chronoamperometry, and cyclic voltammetry in a rotating disk electrode are ideal for studying adhesion of microbes to metallic surfaces. We study the adhesion of Escherichia coli, Bacillus subtilis, and 1 μm silica microspheres over a 0.15 - 37.33 dynes .cm-2 or shear rates of 14.73 - 3727.28 s-1 range. Our results agree with literature on red blood cells in rotating disk electrodes, deposition rates from optical systems, and show that we can quantify changes in active electrode area by bacteria adhesion and protein secretion. These methods measure changes in area instead of mass, are more accurate than fluorescence microscopy, and apply to a larger range of problems than on-chip flow devices.

  6. Perfluorinated compounds in soil, surface water, and groundwater from rural areas in eastern China.

    Science.gov (United States)

    Chen, Shu; Jiao, Xing-Chun; Gai, Nan; Li, Xiao-Jie; Wang, Xiao-Chun; Lu, Guo-Hui; Piao, Hai-Tao; Rao, Zhu; Yang, Yong-Liang

    2016-04-01

    Little research on perfluorinated compounds (PFCs) has been conducted in rural areas, although rural PFC sources are less complicated than in urban and industrial areas. To determine the levels and geographical distribution of 17 PFC compounds, samples of soil, surface water, and groundwater were collected from eight rural areas in eastern China. The total PFC concentrations (∑PFCs) in soils ranged from 0.34 to 65.8 ng/g ∑PFCs in surface waters ranged from 7.0 to 489 ng/L and ∑PFCs in groundwater ranged from 5.3 to 615 ng/L. Ratios of perfluorononanoic acid/perfluorooctanoic acid (PFNA/PFOA), perfluoro-n-butyric acid/perfluorooctanoic acid (PFBA/PFOA), and perfluoroheptanoic acid/perfluorooctanoic acid (PFHpA/PFOA) in rainwater increased due to the fluorine chemical plants in the surrounding rural and urban areas, suggesting that atmospheric precipitation may carry PFCs and their precursors from the fluorochemical industrial area to the adjacent rural areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Isoperimetric surfaces and area-angular momentum inequality in a rotating black hole in new massive gravity

    Science.gov (United States)

    Aceña, Andrés; López, Ericson; Llerena, Mario

    2018-03-01

    We study the existence and stability of isoperimetric surfaces in a family of rotating black holes in new massive gravity. We show that the stability of such surfaces is determined by the sign of the hair parameter. We use the isoperimetric surfaces to find a geometric inequality between the area and the angular momentum of the black hole, conjecturing geometric inequalities for more general black holes.

  8. Determination of water use in Rockford and Kankakee areas, Illinois

    Science.gov (United States)

    LaTour, John K.

    1991-01-01

    Amounts of water withdrawn, delivered, consumed, released, returned, and lost or gained during conveyance were determined for six communities--Rockford, Loves Park, North Park, Kankakee, Bourbonnais, and Bradley--served by the public-water systems in the Rockford and the Kankakee areas of Illinois. Water-use categories studied were commercial, industrial, domestic, and municipal uses; public supply; and sewage treatment. The availability and accuracy of water-use data are described, and water-use coefficients and methods of estimating water use are provided to improve the collection and the analysis of water-use information. Water-use data were obtained from all the water utilities and from 30 major water users in the Rockford and the Kankakee areas. Data were available for water withdrawals by water suppliers; deliveries by water suppliers to water users; returns by sewage-treatment plants and water users; releases by water users to sewers; and sewer-conveyance losses. Accuracy of the water-use data was determined from discharge measurements or reliability tests of water meters, or was estimated according to the completeness of the data. Accuracy of withdrawal and sewage-treatment-return data for the Rockford area and of withdrawal, delivery, industrial release, and sewage-treatment-return data for the Kankakee area was considered to be at least 90 percent. Where water-use data were inadequate or unavailable, various methods were used to estimate consumptive uses; releases; returns by commercial, domestic, and municipal users; and conveyance losses and gains. The methods focused on water budgeting to assure that water uses balanced. Consumptive uses were estimated by use of the consumption-budget method, the types-of-use method, consumptive-use ratios, the winter base-rate method, and the maximum lawn-watering method. The winter base-rate method provided the best domestic consumptive-use estimates, whose ratios (consumptive use from the winter base-rate method

  9. Effect of preparation surface area on the clinical outcome of full veneer crowns in dogs.

    Science.gov (United States)

    Riehl, Jessica; Soukup, Jason W; Collins, Caitlyn; Siverling, Sarah; Ploeg, Heidi-Lynn; Snyder, Christopher J

    2014-01-01

    Crown therapy is commonly used in veterinary medicine to provide support to teeth which have previously fractured, received root canal therapy, have significant wear, or experienced other detrimental removal of tooth substance. As with several aspects of veterinary medicine, many of the recommendations or guidelines for crown therapy originate from human dentistry, which are then transferred to veterinary patients. Due to the significant difference in the anatomy of teeth and function of the oral cavity between humans and dogs, these guidelines need to be studied to determine the appropriateness of their use in veterinary patients. This article evaluates the relationship between surface area of the preparation and clinical outcome of full veneer crown therapy of the canine tooth in dogs. Although there appeared to be a positive relationship between preparations with greater surface area and successful clinical outcome, it was not found to be statistically significant.

  10. Determination of inundation area in the Amazon River floodplain using the SMMR 37 GHz polarization difference

    International Nuclear Information System (INIS)

    Sippel, S.J.; Hamilton, S.K.; Melack, J.M.; Choudhury, B.J.

    1994-01-01

    The 37 GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer (SMMR), which was operated on board the Nimbus-7 satellite, provides a sensitive indicator of surface water. These data can provide information on seasonal inundation patterns in large tropical wetlands such as the Amazon River floodplain. Although the SMMR data are of low resolution, we were able to estimate the area inundated within a group of pixels by using linear mixing models which incorporate the major end-members of the observed microwave signatures. The models were then used to estimate seasonal changes in inundation area over a 7-year period for a 34,550 km 2 area along the Amazon River near Manaus. The seasonal changes in inundation area determined using mixing models correlate well with changes in river stage. (author)

  11. Determination of forest road surface roughness by Kinect depth imaging

    Directory of Open Access Journals (Sweden)

    Francesco Marinello

    2017-12-01

    Full Text Available Roughness is a dynamic property of the gravel road surface that affects safety, ride comfort as well as vehicle tyre life and maintenance costs. A rapid survey of gravel road condition is fundamental for an effective maintenance planning and definition of the intervention priorities.Different non-contact techniques such as laser scanning, ultrasonic sensors and photogrammetry have recently been proposed to reconstruct three-dimensional topography of road surface and allow extraction of roughness metrics. The application of Microsoft Kinect™ depth camera is proposed and discussed here for collection of 3D data sets from gravel roads, to be implemented in order to allow quantification of surface roughness.The objectives are to: i verify the applicability of the Kinect sensor for characterization of different forest roads, ii identify the appropriateness and potential of different roughness parameters and iii analyse the correlation with vibrations recoded by 3-axis accelerometers installed on different vehicles. The test took advantage of the implementation of the Kinect depth camera for surface roughness determination of 4 different forest gravel roads and one well-maintained asphalt road as reference. Different vehicles (mountain bike, off-road motorcycle, ATV vehicle, 4WD car and compact crossover were included in the experiment in order to verify the vibration intensity when travelling on different road surface conditions. Correlations between the extracted roughness parameters and vibration levels of the tested vehicles were then verified. Coefficients of determination of between 0.76 and 0.97 were detected between average surface roughness and standard deviation of relative accelerations, with higher values in the case of lighter vehicles.

  12. Determination of 3D Equilibria from Flux Surface Knowledge Only

    International Nuclear Information System (INIS)

    Mynick, H.E.; Pomphrey, N.

    2001-01-01

    We show that the method of Christiansen and Taylor, from which complete tokamak equilibria can be determined given only knowledge of the shape of the flux surfaces, can be extended to 3-dimensional equilibria, such as those of stellarators. As for the tokamak case, the given geometric knowledge has a high degree of redundancy, so that the full equilibrium can be obtained using only a small portion of that information

  13. Effect of impervious surface area and vegetation changes on mean ...

    African Journals Online (AJOL)

    adeniyi adeyemi

    sprawl and this has contributed to increase in surface temperature. Keyword: Thematic indices, surface temperature, Landsat, vegetation, ISA, Tshwane Metropolis. 1. Introduction. Globally, rapid increase in population in major cities has led to urban sprawl at an unprecedented rate which is, according to the analysis and ...

  14. Determination of the photoelectron reference plane in nanostructured surfaces

    International Nuclear Information System (INIS)

    Lobo-Checa, Jorge; Mugarza, Aitor; Ortega, Jose Enrique; Michel, Enrique G

    2011-01-01

    In angle-resolved photoemission (ARPES) from crystalline solids, wave-vector conservation applies to the two-dimensional (2D) surface, which may thus be defined as the reference plane in ARPES. We investigate whether such reference varies for photoemitted electrons in nanometer-sized systems that expose different crystal planes. To this aim, we exploit the structural tunability of the Ag/Cu(223) system which is capable of offering surfaces with periodic arrays of nanofacets of varying size and orientation. A thorough, photon-energy-dependent analysis of the surface states confined to such nanostructures is performed comparing different reference planes for photoemitted electrons. Assuming the premise that k || must be a good quantum number for 2D states, we conclude that the (final state) photoelectron reference direction is not the average optical direction but the local facet that confines the (initial state) surface electrons. Moreover, in the general case of nanostructured systems with uneven surfaces, we show how the photoelectron reference plane can be empirically determined through such a photon-energy-dependent ARPES analysis. (paper)

  15. Analysis and Application of River Surface Line in Hilly Area based on Hec-ras Model

    Directory of Open Access Journals (Sweden)

    Yang Congshan

    2017-01-01

    Full Text Available For example—Cixian Fuyang River Regulation Project. Due to the character that Fuyang River is located in hilly areas of Cixian, we use the Hex-ras software to calculate the status of the river water surface line for the goal of determining the final treatment plan. We maintain the present situation of the river channel design as principle, select the most appropriate pushed water level and roughnessas the basic, and we combine the classification calculation of crossing structures of backwater and the encryption calculation section to get the more accurate result. We compare the water level elevation and the calculation of cross strait, analyze the design parameters, calculate repeated the water line section, analyze the rationality of the design plan, and then finally determine the applicability of Hex-rac software in the large continuous variation of cross section of embankment of river river surface line.

  16. Adsorption of neon and tetrafluoromethane on carbon nanohorn aggregates: differences in specific surface area values

    Science.gov (United States)

    Krungleviciute, Vaiva; Yudasaka, Masako; Iijima, Sumio; Migone, Aldo

    2008-03-01

    We have measured adsorption isotherms for two different adsorbates, neon and tetrafluoromethane, on dahlia-like carbon nanohorn aggregates. The experiments were performed at similar relative temperatures for both gases. The measurements were conducted to explore the effect of adsorbate diameter on the behavior of the resulting adsorbed systems. We measured the effective specific surface area value of the nanohorn sample using both gases, and we found that this quantity was about 22% smaller when we determined this quantity using tetrafluoromethane, the larger molecule. Isosteric heat and binding energy values were also determined from our measurements. We will compare our experimental results with those from a computer simulation study performed by Prof. M. Calbi. The simulations help us understand the source of the observed differences in the measured specific surface values, as well as the coverage dependence of the isosteric heat of adsorption for both gases.

  17. SMAPVEX12 Surface Roughness Data for Agricultural Area V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains surface roughness data collected at several agricultural sites as a part of the Soil Moisture Active Passive Validation Experiment 2012...

  18. Geotechnical properties of surface sediments in the INDEX area

    Digital Repository Service at National Institute of Oceanography (India)

    Khadge, N.H.

    As a part of the environmental impact assessment studies, geotechnical properties of sediments were determined in the Central Indian Basin. The undrained shear strength and index properties of the siliceous sediments were determined on 20 box cores...

  19. Experimental determinations of the performances of heat transfer surfaces

    International Nuclear Information System (INIS)

    Pirovano, Alain; Viannay, Stephane; Mazeas, C.Y.

    1974-01-01

    With the help of flow schemes and of assumptions on the heat transfer, it is possible, in some cases, to predict the thermal and aerodynamical performances of a new heat transfer surface with moderate accuracy. These estimates, valid for an approximate classification of a new surface among known surfaces, are not accurate enough to be taken as a basis for the design of heat exchangers. In the present state of knowledge, the performances of a new heat transfer surface can only be determined accurately with experimental measurements. Bertin and Co have at their disposal two air test rigs especially designed for this purpose. The first one, more directly concerned with the measurements on tube bundles with fluid flow perpendicular to the generatrices of the tubes, is a semi-closed loop equipped with a high-efficiency ejector which amplifies the air flow rate supplied by an external source and thus allows high values of Reynolds number to be reached. The second one is adapted to other types of surfaces: tubes with external flow parallel to the generatrices, tubes with sophisticated cross section and with internal flow, compact surfaces with finned plates, etc. Both test rigs, the relevant equipment, the methods of data acquisition and of test results analysis are described in this paper. During the 5 past years, 60 configurations were tested. It was possible to compare some of the test results with the results of measurements performed later, on entire heat exchangers working with numbers of tubes, fluids, and temperature levels different from those prevailing during the tests on the small scale mock-up; the agreement is quite good [fr

  20. Properties that influence the specific surface areas of carbon nanotubes and nanofibers.

    Science.gov (United States)

    Birch, M Eileen; Ruda-Eberenz, Toni A; Chai, Ming; Andrews, Ronnee; Hatfield, Randal L

    2013-11-01

    Commercially available carbon nanotubes and nanofibers were analyzed to examine possible relationships between their Brunauer-Emmett-Teller specific surface areas (SSAs) and their physical and chemical properties. Properties found to influence surface area were number of walls/diameter, impurities, and surface functionalization with hydroxyl and carboxyl groups. Characterization by electron microscopy, energy-dispersive X-ray spectrometry, thermogravimetric analysis, and elemental analysis indicates that SSA can provide insight on carbon nanomaterials properties, which can differ vastly depending on synthesis parameters and post-production treatments. In this study, how different properties may influence surface area is discussed. The materials examined have a wide range of surface areas. The measured surface areas differed from product specifications, to varying degrees, and between similar products. Findings emphasize the multiple factors that influence surface area and mark its utility in carbon nanomaterial characterization, a prerequisite to understanding their potential applications and toxicities. Implications for occupational monitoring are discussed.

  1. Determining the limit of detection of surface bound antibody.

    Science.gov (United States)

    Madiona, Robert M T; Welch, Nicholas G; Scoble, Judith A; Muir, Benjamin W; Pigram, Paul J

    2017-08-11

    Determination of a limit of detection (LoD) for surface bound antibodies is crucial for the development and deployment of sensitive bioassays. The measurement of very low concentrations of surface bound antibodies is also important in the manufacturing of pharmaceutical products such as antibody-conjugated pharmaceuticals. Low concentrations are required to avoid an immune response from the target host. Enzyme-linked immunosorbent assay (ELISA), x-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were used to determine the LoD for the surface bound antibody (antiepidermal growth factor receptor antibody) on silicon substrates. Antibody solution concentrations between 10 μg/ml and 1 ng/ml and a control (antibody-free buffer solution) were employed, and the detection performance of each technique was compared. For this system, the ELISA LoD was 100 ng/ml and the XPS LoD was 1 μg/ml, corresponding to an estimated surface concentration of 49  ± 7 ng/cm 2 using a 1 μg/ml solution. Due to the multivariate complexity of ToF-SIMS data, analysis was carried out using three different methods, peak ratio calculations, principal component analysis, and artificial neural network analysis. The use of multivariate analysis with this dataset offers an unbiased analytical approach based on the peaks selected from ToF-SIMS data. The results estimate a ToF-SIMS LoD between applied antibody concentrations of 10 and 100 ng/mL. For surface bound antibodies on a silicon substrate, the LoD is below an estimated surface concentration of 49 ng/cm 2 . The authors have determined the LoD for this system using ELISA, XPS, and ToF-SIMS with multivariate analyses, with ToF-SIMS offering an order of magnitude better detection over ELISA and 2 orders of magnitude better detection over XPS.

  2. Effects of raw material texture and activation manner on surface area of porous carbons derived from biomass resources.

    Science.gov (United States)

    Zhang, Feng; Li, Guo-Dong; Chen, Jie-Sheng

    2008-11-01

    Porous carbons have been prepared from biomass resources, such as cornstalks, rice straws, pine needles and pinecone hulls, through a simple carbonization and KOH solution activation process. The pore sizes of the obtained porous carbons are mainly distributed in the range of 1-2 nm, whereas the surface areas of the materials vary from 1000 to more than 3000 m(2) g(-1) depending on the raw materials and preparation conditions. It is found that the biomass texture and the activation manner play key roles in determination of surface areas of the porous carbons. In addition, the amount of activation agent, the activation temperature and the activation time also affect the surface area of the porous carbons but to a less extent. The obtained porous carbons with high surface areas show good performance when used as Pt-catalyst supports for cinanamaldehyde hydrogenation.

  3. High-surface-area silica nanospheres (KCC-1) with a fibrous morphology

    KAUST Repository

    Polshettiwar, Vivek

    2010-08-02

    Fibrous nanosilica: A new family of high-surface-area silica nanospheres (KCC-1) have been prepared (see picture). KCC-1 features excellent physical properties, including high surface area, unprecedented fibrous surface morphology, high thermal (up to 950 °C) and hydrothermal stabilities, and high mechanical stability. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Lung deposited surface area concentrations in a street canyon

    Science.gov (United States)

    Kuuluvainen, Heino; Hietikko, Riina; Järvinen, Anssi; Saukko, Erkka; Irjala, Matti; Niemi, Jarkko V.; Timonen, Hilkka; Keskinen, Jorma; Rönkkö, Topi

    2017-04-01

    Street canyons are interesting environments with respect to the dispersion of traffic emissions and human exposure. Pedestrians may be exposed to relatively high concentrations of fine particles and the vertical dispersion affects the human exposure above the ground level in buildings. Previously, particle concentrations have been measured in street canyons at a few different heights (Marini et al., 2015). The information on the lung deposited surface area (LDSA) concentration, which is a relevant metric for the negative health effects, is very limited even at the ground level of street canyons (Kuuluvainen et al., 2016). More information especially on the vertical dispersion and the ground level concentrations is needed, for instance, for the use of urban planning and the design of ventilation systems in buildings. Measurements were carried out in a busy street canyon in Helsinki, Finland, at an urban super-site measurement station (Mäkelänkatu 50). The data included vertical concentration profiles measured in an intensive measurement campaign with a Partector (Naneos GmbH) installed into a drone, long-term measurements with an AQ Urban particle sensor (Pegasor Ltd.), and an extensive comparison measurement in the field with different devices measuring the LDSA. These devices were an AQ Urban, Partector, DiSCmini (Testo AG), NSAM (TSI Inc.), and an ELPI+ (Dekati Ltd.). In addition, continuous measurements of gas phase components, particle size distributions, and meteorology were run at the supersite. The vertical profile measurements were con-ducted in November 2016 during two days. In the measurements, the drone was flown from the ground level to an altitude of 50 or 100 m, which is clearly above the roof level of the buildings. Altogether, 48 up-and-down flights were conducted during the two days. The vertical profiles were supported by continuous measurements at the ground level on both sides of the street canyon. The long-term measurements were conducted

  5. Structure determination by photoelectron diffraction of small molecules on surfaces

    International Nuclear Information System (INIS)

    Booth, N.A.

    1998-05-01

    The synchrotron radiation based technique of Photoelectron Diffraction (PhD) has been applied to three adsorption systems. Structure determinations, are presented for each system which involve the adsorption of small molecules on the low index {110} plane of single crystal Cu and Ni substrates. For the NH 3 -Cu(110) system PhD was successful in determining a N-Cu bondlength of 2.05 ± 0.03 A as well as values for the anisotropic vibrational amplitudes of the N and an expansion of the 1st to 2nd Cu substrate layer spacing from the bulk value of 0.08 ± 0.08 A. The most significant and surprising structural parameter determined for this system was that the N atom occupies an asymmetric adsorption site. Rather than being situated in the expected high symmetry atop site the N atom was found to be offset parallel to the surface by 0.37 ± 0.12 A in the [001] azimuth. In studying the glycine-Cu(110) system the adsorption structure of an amino-acid has been quantified. The local adsorption geometries of all the atoms involved in the molecule to surface bond have been determined. The glycine molecule is found to be bonded to the surface via both its amino and carboxylate functional groups. The molecule straddles two [11-bar0] rows of the Cu substrate. The two O atoms are found to be in identical sites both approximately atop Cu atoms on the [11-bar0] rows offset parallel to the surface by 0.80 ± 0.05 A in the [001] azimuth, the O-Cu bondlength was found to be 2.03 ± 0.05 A. The N atom was also found to adsorb in an approximately atop geometry but offset parallel to the surface by 0.24 ± 0.10A in the [11-bar0] direction, the N-Cu bondlength was found to be 2.05± 0.05 A. PhD was unsuccessful in determining the positions of the two C atoms that form a bridge between the two functional groups bonded to the surface due to difficulties in separating the two inequivalent contributions to the final intensity modulation function. For the CN-Ni(110) system both PhD and Near Edge

  6. Determination of Contact Angle from Contact Area of Liquid Droplet Spreading on Solid Substrate

    Directory of Open Access Journals (Sweden)

    Rhoda H. GUMUS

    2007-01-01

    Full Text Available Both complete and incomplete wetting were considered for the spreading of liquid drops on solid substrate. The liquid droplets were silicone oil, glycerine and hexadecane and the solid substrates are glass, polystyrene and polymethyl methacrylate (PMMA. Wetting was characterized by measuring the contact angle formed between the liquid drop and solid surface. Small droplets of constant volume were used for the measurements in order to minimize gravitational effects. The contact radius was obtained as a function of time by an image analysis system and used for the calculation of the contact area. The contact area was then used to determine the contact angle. The contact angles calculated from contact area are in good agreement with the experimental values.

  7. Military Surface Grid Areas: Atlantic / Gulf of Mexico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regular pattern of polygons that represent arbitrary delineations of an Operating Area (OPAREA). The MarineCadastre.gov team worked with the Navy to provide this...

  8. Quantifying the effect of waterways and green areas on the surface temperature

    Directory of Open Access Journals (Sweden)

    Elis Dener Lima Alves

    2017-02-01

    Full Text Available The cooling effects of urban parks and green areas, which form the “Park Cool Island” (PCI can help decrease the surface temperature and mitigate the effects of urban heat islands (UHI. Therefore, the objective of this research was to know the temporal variability of PCI intensity, as well as analyze the factors that determines it and propose an equation to predict the PCI intensity in Iporá, Goiás State, Brazil. To this purpose, the PCI intensity values were obtained using the Landsat-8 satellite (band 10, and then correlated with the NDVI and the LAI, in which proposes equations through multiple linear regression to estimate the PCI intensity. The results indicated that: 1 the greater the distance of the natural area, greater the surface temperature; 2 there is a great seasonality in PCI, in which the intensity of PCI is much higher in the spring (or close to it; 3 the relationship between NDVI and LAI variables, showed good coefficients of determination; 4 the equations for the buffer of 200 and 500 m, had low RMSE with high coefficients of determination (r2 = 0.924 and r2 = 0.957 respectively.

  9. 30 CFR 910.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 910.764 Section 910.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE GEORGIA § 910.764 Process for designating areas unsuitable for surface coal mining...

  10. 30 CFR 937.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 937.764 Section 937.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE OREGON § 937.764 Process for designating areas unsuitable for surface coal mining...

  11. 30 CFR 947.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 947.762 Section 947.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining and reclamation operations. ...

  12. 30 CFR 921.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 921.762 Section 921.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mine operations. ...

  13. 30 CFR 922.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 922.764 Section 922.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE MICHIGAN § 922.764 Process for designating areas unsuitable for surface coal mining...

  14. 30 CFR 942.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 942.764 Section 942.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE TENNESSEE § 942.764 Process for designating areas unsuitable for surface coal mining... Mining Operations, shall apply to surface coal mining and reclamation operations. (b) The Secretary shall...

  15. 30 CFR 941.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 941.764 Section 941.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE SOUTH DAKOTA § 941.764 Process for designating areas unsuitable for surface coal mining...

  16. 30 CFR 941.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 941.762 Section 941.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mine operations. ...

  17. 30 CFR 939.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 939.764 Section 939.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE RHODE ISLAND § 939.764 Process for designating areas unsuitable for surface coal mining...

  18. 30 CFR 933.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 933.762 Section 933.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designation Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining and reclamation operations. ...

  19. 30 CFR 939.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 939.762 Section 939.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining and reclamation operations. ...

  20. 30 CFR 905.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 905.762 Section 905.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining operations. ...

  1. Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada

    International Nuclear Information System (INIS)

    1999-01-01

    This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 417: Central Nevada Test Area Surface, Nevada, under the Federal Facility Agreement and Consent Order. Located in Hot Creek Valley in Nye County, Nevada, and consisting of three separate land withdrawal areas (UC-1, UC-3, and UC-4), CAU 417 is comprised of 34 corrective action sites (CASs) including 2 underground storage tanks, 5 septic systems, 8 shaker pad/cuttings disposal areas, 1 decontamination facility pit, 1 burn area, 1 scrap/trash dump, 1 outlier area, 8 housekeeping sites, and 16 mud pits. Four field events were conducted between September 1996 and June 1998 to complete a corrective action investigation indicating that the only contaminant of concern was total petroleum hydrocarbon (TPH) which was found in 18 of the CASs. A total of 1,028 samples were analyzed. During this investigation, a statistical approach was used to determine which depth intervals or layers inside individual mud pits and shaker pad areas were above the State action levels for the TPH. Other related field sampling activities (i.e., expedited site characterization methods, surface geophysical surveys, direct-push geophysical surveys, direct-push soil sampling, and rotosonic drilling located septic leachfields) were conducted in this four-phase investigation; however, no further contaminants of concern (COCs) were identified. During and after the investigation activities, several of the sites which had surface debris but no COCs were cleaned up as housekeeping sites, two septic tanks were closed in place, and two underground storage tanks were removed. The focus of this CADD was to identify CAAs which would promote the prevention or mitigation of human exposure to surface and subsurface soils with contaminant

  2. Surface albedo measurements in Mexico City metropolitan area

    Energy Technology Data Exchange (ETDEWEB)

    Castro, T; Mar, B; Longoria, R; Ruiz Suarez, L. G [Centro de Ciencias de la Atmosfera, UNAM, Mexico, D.F. (Mexico); Morales, L [Instituto de Geografia, UNAM, Mexico, D.F. (Mexico)

    2001-04-01

    Optical and thermal properties of soils are important input data for the meteorological and photochemical modules of air quality models. As development of these models increase on spatial resolution good albedo data become more important. In this paper measurements of surface albedo of UV (295-385 nm) and visible (450-550 nm) radiation are reported for different urban and rural surfaces in the vicinity of Mexico City. It was found for the downtown zone and average albedo value of 0.05 which is in very good agreement with reported values for urban surfaces. Our albedo values measured in UV region for grey cement and green grass are of 0.10 and 0.009, respectively, and quite similar to those found at the literature of 0.11 and 0.008 for those type of surfaces. [Spanish] Las propiedades opticas y termicas de suelos son datos importantes para los modulos meteorologicos y fotoquimicos de los modelos de calidad del aire. Conforme aumenta la resolucion espacial del modelo se vuelve mas importante contar con buenos datos de albedo. En este articulo se presentan mediciones de albedo superficial de radiacion Ultravioleta (295-385 nm) y visible (450-550 nm) para diferentes superficies urbanas. Los valores medidos de albedo en la region UV para cemento gris y pasto verde son de 0.10 y 0.009, respectivamente, y son muy similares a los reportados en la literatura, 0.11 y 0.008 para este tipo de superficies.

  3. Determination Of Segmented Angular Shapes For Circular Areas Of ...

    African Journals Online (AJOL)

    Stable Food Crops Turning Into Commercial Crops: Case studies of Teff, Wheat and Rice in Ethiopia Most thermal equipment like industrial boilers, ceramic kilns, incinerators, thermal plants for electricity generation, have specially designed circular areas through which heat passes or generates. Since these areas are ...

  4. Large Area Diamond Tribological Surfaces with Negligible Wear in Extreme Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase I we propose to demonstrate the processing of very large area diamond sliding bearings and tribological surfaces. The bearings and surfaces will experience...

  5. Determination of the Priority Aspect in Process of Determining Urban Residential Area

    Science.gov (United States)

    Bhekti Pribadi, Cherie; Hariyanto, Teguh

    2017-12-01

    Recently, the population growth is increasingly crowded in urban area and as a source of land supply for housing development into the needs of each individual becomes increasingly limited. the home is one of the basic rights of the people and therefore every citizen has the right to reside and got a good environment and healthy. Besides the house is also a basic human need to enhance the dignity, the dignity, quality of life and livelihood, as well as personal self-reflection in order to improve the standard of living, as well as the formation of character, character and personality of the nation. The construction of such housing should always take into consideration many aspects in order to create a balanced environment not only based on the suitability of land but also based on the aspects that exist in surrounding. Therefore, this study will be to analyze the priority aspect in process of determining urban residential area using Analytical Hierarchy Process Method. This method aims to determine priority aspect were used based on primary data collection form of questionnaires and interviews to respondents who expert in the field.

  6. Estimating the surface area of birds: using the homing pigeon (Columba livia) as a model.

    Science.gov (United States)

    Perez, Cristina R; Moye, John K; Pritsos, Chris A

    2014-05-08

    Estimation of the surface area of the avian body is valuable for thermoregulation and metabolism studies as well as for assessing exposure to oil and other surface-active organic pollutants from a spill. The use of frozen carcasses for surface area estimations prevents the ability to modify the posture of the bird. The surface area of six live homing pigeons in the fully extended flight position was estimated using a noninvasive method. An equation was derived to estimate the total surface area of a pigeon based on its body weight. A pigeon's surface area in the fully extended flight position is approximately 4 times larger than the surface area of a pigeon in the perching position. The surface area of a bird is dependent on its physical position, and, therefore, the fully extended flight position exhibits the maximum area of a bird and should be considered the true surface area of a bird. © 2014. Published by The Company of Biologists Ltd | Biology Open.

  7. Comparison of diffusion charging and mobility-based methods for measurement of aerosol agglomerate surface area.

    Science.gov (United States)

    Ku, Bon Ki; Kulkarni, Pramod

    2012-05-01

    We compare different approaches to measure surface area of aerosol agglomerates. The objective was to compare field methods, such as mobility and diffusion charging based approaches, with laboratory approach, such as Brunauer, Emmett, Teller (BET) method used for bulk powder samples. To allow intercomparison of various surface area measurements, we defined 'geometric surface area' of agglomerates (assuming agglomerates are made up of ideal spheres), and compared various surface area measurements to the geometric surface area. Four different approaches for measuring surface area of agglomerate particles in the size range of 60-350 nm were compared using (i) diffusion charging-based sensors from three different manufacturers, (ii) mobility diameter of an agglomerate, (iii) mobility diameter of an agglomerate assuming a linear chain morphology with uniform primary particle size, and (iv) surface area estimation based on tandem mobility-mass measurement and microscopy. Our results indicate that the tandem mobility-mass measurement, which can be applied directly to airborne particles unlike the BET method, agrees well with the BET method. It was also shown that the three diffusion charging-based surface area measurements of silver agglomerates were similar within a factor of 2 and were lower than those obtained from the tandem mobility-mass and microscopy method by a factor of 3-10 in the size range studied. Surface area estimated using the mobility diameter depended on the structure or morphology of the agglomerate with significant underestimation at high fractal dimensions approaching 3.

  8. GC/MS Analysis of Pesticides in the Ferrara Area (Italy) Surface Water: A Chemometric Study

    International Nuclear Information System (INIS)

    Pasti, L.; Dondi, F.; Nava, E.; Morelli, M.; Bignami, S.

    2007-01-01

    The development of a network to monitor surface waters is a critical element in the assessment, restoration and protection of water quality. In this study, concentrations of 42 pesticides - determined by GC-MS on samples from 11 points along the Ferrara area rivers - have been analyzed by chemometric tools. The data were collected over a three-year period (2002-2004). Principal component analysis of the detected pesticides was carried out in order to define the best spatial locations for the sampling points. The results obtained have been interpreted in view of agricultural land use. Time series data regarding pesticide contents in surface waters has been analyzed using the Autocorrelation function. This chemometric tool allows for seasonal trends and makes it possible to optimize sampling frequency in order to detect the effective maximum pesticide content

  9. A NEW THEORETICAL DETERMINATION OF YIELD STRESS BASED ON THE CONCEPT OF EFFICIENT AREA OF STRESS

    OpenAIRE

    A BENMOHAMMED; M OUALI

    2000-01-01

    This study presents a new theoretical determination of yield stress for pure mono-crystal materials based on the concept of the Efficient Area of Stress (EAS). From the atomic yield stress on the atomic surface a², given by the model of Orowan, the macroscopic yield stress is then obtained through a Scale Law of Measure (SLM) which depends only on the lattice spacing and a constant L. This relation shows that the efficient atomic dimension is a fractal dimension. The precision obtained by the...

  10. Assessment of large aperture scintillometry for large-area surface ...

    Indian Academy of Sciences (India)

    29

    This study defines that large aperture scintillometer is robust instrument which can evaluate energy flux over a large area with a long term series time domain. Moreover, further studied should be conducted to use in crop simulation modelling, developing of new model with calibration and validation of remote sensing energy ...

  11. Albedo and land surface temperature shift in hydrocarbon seepage potential area, case study in Miri Sarawak Malaysia

    International Nuclear Information System (INIS)

    Suherman, A; Rahman, M Z A; Busu, I

    2014-01-01

    The presence of hydrocarbon seepage is generally associated with rock or mineral alteration product exposures, and changes of soil properties which manifest with bare development and stress vegetation. This alters the surface thermodynamic properties, changes the energy balance related to the surface reflection, absorption and emission, and leads to shift in albedo and LST. Those phenomena may provide a guide for seepage detection which can be recognized inexpensively by remote sensing method. District of Miri is used for study area. Available topographic maps of Miri and LANDSAT ETM+ were used for boundary construction and determination albedo and LST. Three land use classification methods, namely fixed, supervised and NDVI base classifications were employed for this study. By the intensive land use classification and corresponding statistical comparison was found a clearly shift on albedo and land surface temperature between internal and external seepage potential area. The shift shows a regular pattern related to vegetation density or NDVI value. In the low vegetation density or low NDVI value, albedo of internal area turned to lower value than external area. Conversely in the high vegetation density or high NDVI value, albedo of internal area turned to higher value than external area. Land surface temperature of internal seepage potential was generally shifted to higher value than external area in all of land use classes. In dense vegetation area tend to shift the temperature more than poor vegetation area

  12. Investigation on the growth of DAST crystals of large surface area for THz applications

    International Nuclear Information System (INIS)

    Vijay, R. Jerald; Melikechi, N.; Thomas, Tina; Gunaseelan, R.; Arockiaraj, M. Antony; Sagayaraj, P.

    2012-01-01

    Graphical abstract: It is evident from the photographs that the crystal tend to grow as a needle (Fig. 1a) in the lower concentration region (2–3 g/200 mL); whereas, in the high concentration region (5 g/200 mL) though there is a marked enlargement in the size of the crystal, the morphology of the resulting DAST crystal is slightly irregular (Fig. 1d) in nature. Among the four concentrations employed, best result was obtained with the DAST–methanol solution of concentration 4 g/200 mL; which resulted in the DAST crystal of large surface area (270 mm 2 ) with high transparency and nearly square shape (Fig. 1c) in a growth period of 20–25 days. Highlights: ► DAST crystals of different sizes are obtained for different concentrations. ► The main focus is to grow DAST crystals with large surface area. ► Structural, optical, thermal and mechanical properties are investigated. - Abstract: The growth of high quality 4-N,N-dimethylamino-4-N-methyl-stilbazoliumtosylate (DAST) crystal with large surface area is reported by adopting the slope nucleation coupled slow evaporation method (SNM-SE). The structure and composition of the crystal are studied by single crystal X-ray diffraction and CHN analyses. The linear optical properties are investigated by UV–vis absorption. The melting point and thermal behavior of DAST are investigated using differential scanning calorimetric (DSC) and thermogravimetric analyses (TGA). The Vickers microhardness number (VHN) and work hardening coefficient of the grown crystal have been determined. The surface features of the DAST crystal are analyzed by scanning electron microscopy (SEM) and it confirmed the presence of narrow line defects (NLDs) in the sample.

  13. Measuring the Determinants of Relative Economic Performance of Rural Areas

    Science.gov (United States)

    Agarwal, Sheela; Rahman, Sanzidur; Errington, Andrew

    2009-01-01

    This paper examines the determinants of economic performance of 149 English rural Local Authority Districts (LADs). A Three Stage Least Square (3SLS) estimation procedure was employed to jointly determine the influence of a wide range of indicators representing economic, human, cultural and environmental capital, as well as less tangible or…

  14. Metal pollution determined by pollution indices for sea grass P. oceanica and surface sediments

    Directory of Open Access Journals (Sweden)

    Stanković Slavka

    2015-01-01

    Full Text Available Concentrations of Fe, Mn, Cu, Zn, Pb, Ni, Co, As, Co, and Hg in the sea grass Posidonia oceanica and surface sediment samples were determined. Together with P. oceanica, surface sediment samples were collected at eight locations in the major demographic, tourist and port areas along the Montenegrin coast to assess metal pollution. The metal pollution index (MPI and metal enrichment factor (EF were calculated and used to evaluate the impact of heavy metals in the surface sediment on P. oceanica. The sediment MPI and EF values were lower than these values in P. oceanica at the same locations. Since the surface sediment contained lower mean concentrations of Zn, Ni, Pb, Cd and Hg, than the sea grass P. oceanic, we concluded that the sea grass absorbed some metals from the seawater column. [Projekat Ministarstva nauke Republike Srbije, br. III 43009

  15. Study of the mobility, surface area, and sintering behavior of agglomerates in the transition regime by tandem differential mobility analysis

    International Nuclear Information System (INIS)

    Cho, Kuk; Hogan, Christopher J.; Biswas, Pratim

    2007-01-01

    The surface area of nanosized agglomerates is of great importance as the reactivity and health effects of such particles are highly dependent on surface area. Changes in surface area through sintering during nanoparticle synthesis processes are also of interest for precision control of synthesised particles. Unfortunately, information on particle surface area and surface area dynamics is not readily obtainable through traditional particle mobility sizing techniques. In this study, we have experimentally determined the mobility diameter of transition regime agglomerates with 3, 4, and 5 primary particles. Agglomerates were produced by spray drying well-characterised polystyrene latex particles with diameters of 55, 67, 76, and 99 nm. Tandem differential mobility analysis was used to determine agglomerate mobility diameter by selecting monodisperse agglomerates with the same number of primary particles in the first DMA, and subsequently completely sintering the agglomerates in a furnace aerosol reactor. The size distribution of the completely sintered particles was measured by an SMPS system, which allowed for the determination of the number of primary particles in the agglomerates. A simple power law regression was used to express mobility diameter as a function of primary particle size and the number of primary particles, and had an excellent correlation (R 2 = 0.9971) with the experimental data. A scaling exponent was determined from the experimental data to relate measured mobility diameter to surface area for agglomerates. Using this relationship, the sintering characteristics of agglomerates were also examined for varying furnace temperatures and residence times. The sintering data agreed well with the geometric sintering model (GSM) model proposed by Cho and Biswas (2006a) as well as with the model proposed Koch and Friedlander (1990) for sintering by viscous flow

  16. Evolution of surface area-to-volume ratio for a water meniscus evaporating between contacting silica spheres.

    Science.gov (United States)

    Cutts, R E; Burns, S E

    2010-03-01

    An experimental investigation was performed under isothermal conditions to quantify the rate of evaporation of water from a receding pendular meniscus connecting two silica spheres. Optically based measurements were used to determine the relevant meniscus dimensions, and the meniscus was modeled using a toroidal approximation. The rate of change of meniscus surface area and volume was then predicted using mathematical modeling software. The results demonstrated that once the meniscus transitioned from a relatively flat surface to one with an increasing radius of curvature, the rate of change of the ratio of surface area-to-volume was relatively constant over the range of water contents that were observable using the optical investigation techniques implemented in this study. Comparison of the flux of water from the meniscus surface demonstrated that the evaporation of bound water was four orders of magnitude slower than evaporation from a free water surface. 2009 Elsevier Inc. All rights reserved.

  17. Effect of surface area and air-drying distance on shear bond strength of etch-and-rinse adhesive

    Directory of Open Access Journals (Sweden)

    Farid Mohammed Sabry El-Askary

    2012-10-01

    Full Text Available We evaluated the effects of air-drying distance and bond surface area on the shear bond strength of a 2-step etch-and-rinse adhesive. A total of 120 bovine anterior teeth were equally divided into 6 main groups based on bonding surface area. The main groups were divided into sub-groups (n = 5 according to air-drying distance. The shear strength was determined using a universal testing machine at a crosshead speed of 0.5 mm/min. The averaged results were subjected to two-way ANOVA and Tukey's test (α = 0.05. Two-way ANOVA testing identified no significant cross-product interactions (p > 0.05, but the main factors of area (p < 0.0001 and air-drying distance (p < 0.00001 significantly affected the mean bond strength. Shorter air-drying distances improved bond strength, and increased surface area decreased the bond strength.

  18. Comparison of sorption capacity and surface area of activated ...

    African Journals Online (AJOL)

    Ash content and percentage fixed carbon were determined for two of the activated carbons (JPS and JCS) with the highest adsorptive capacity. Equilibrium study on adsorption was carried out and the adsorption data were analyzed using the Langmuir isotherm. The results obtained indicate that activated carbons from the ...

  19. comparison of sorption capacity and surface area of activated

    African Journals Online (AJOL)

    Preferred Customer

    ABSTRACT. Activated carbons were prepared from fruit pericarp and seed coat of Jatropha curcas using. KOH and NaCl as activating agents leading to the production of four samples of activated carbons JPS, JPP, JCS and JCP. The adsorption capacity based on adsorption of methylene blue was determined for each ...

  20. Minimal area surfaces in AdS n+1 and Wilson loops

    Science.gov (United States)

    He, Yifei; Huang, Changyu; Kruczenski, Martin

    2018-02-01

    The AdS/CFT correspondence relates the expectation value of Wilson loops in N = 4 SYM to the area of minimal surfaces in AdS 5. In this paper we consider minimal area surfaces in generic Euclidean AdS n+1 using the Pohlmeyer reduction in a similar way as we did previously in Euclidean AdS 3. As in that case, the main obstacle is to find the correct parameterization of the curve in terms of a conformal parameter. Once that is done, the boundary conditions for the Pohlmeyer fields are obtained in terms of conformal invariants of the curve. After solving the Pohlmeyer equations, the area can be expressed as a boundary integral involving a generalization of the conformal arc-length, curvature and torsion of the curve. Furthermore, one can introduce the λ-deformation symmetry of the contours by a simple change in the conformal invariants. This determines the λ-deformed contours in terms of the solution of a boundary linear problem. In fact the condition that all λ deformed contours are periodic can be used as an alternative to solving the Pohlmeyer equations and is equivalent to imposing the vanishing of an infinite set of conserved charges derived from integrability.

  1. DETERMINANTS OF EDUCATIONAL ADVANCEMENT OF RURAL AREAS IN POLAND

    Directory of Open Access Journals (Sweden)

    Anna Mijal

    2017-03-01

    Full Text Available  The article is an aimed attempt at the diagnosis and evaluation of the educational level (character of rural population in Poland perceived as educational advancement as well as of its environment (background. Growing importance of education in improving professional opportunities, changing educational aspirations and parents’ support as well as positive internal migration trends were emphasised. Rural regions are still lagging behind urban areas, though optimistic characteristics indicate receding stigmatisation and marginalisation of the Polish country with internal migration of young and educated individuals, including affluent ones (potential luxury goods buyers, to rural areas. In the semi urbanisation and suburbanisation processes the increase of rural population involves mostly areas adjacent to big agglomerations rather than peripheral villages. The study is based on analysis of public statistical Central Statistical Office of Poland data including the National Population and Housing Censuses of 1988, 2002, 2011, supplemented and deepened the Public Opinion Research Center (CBOS opinion poll results in Poland and global reports from the area of urbanization and education.

  2. Quality Assurance in the Determination of Overlapping Peak Areas

    DEFF Research Database (Denmark)

    Christensen, L.H.; Heydorn, K.

    1987-01-01

    The ability of different computer programs to yield accurate peak areas in statistical control in the case of partially overlapping photopeaks has been tested by the Analysis of Precision. A modified Covell method, two commercially available peak-fitting programs from Nuclear Data and Ortec, and ...

  3. Determination of the upper limit of a peak area

    International Nuclear Information System (INIS)

    Helene, O.

    1990-03-01

    This paper reports the procedure to extract an upper limit of a peak area in a multichannel spectrum. This procedure takes into account the finite shape of the peak and the uncertanties in the background and in the expected position of the peak. (author) [pt

  4. The measurement of surface roughness to determine the suitability of different methods for stone cleaning

    International Nuclear Information System (INIS)

    Vazquez-Calvo, Carmen; Alvarez de Buergo, Monica; Fort, Rafael; Varas-Muriel, Maria Jose

    2012-01-01

    The roughness of stone surface was measured, before and after bead blasting-based cleaning methods, to select the most efficient one to be used in masonry and stonework of specific areas of the Cathedral of Segovia (Spain). These types of cleaning methods can, besides the removal of soiling and surface deposits, leave a rougher surface, which would mean higher and more rapid water retention and deposit accumulation due to a specific surface increase, therefore accelerating stone decay. Or, in contrast, the cleaning method can be so aggressive that it can smooth the surface by reducing its roughness, a fact that usually corresponds to excessive material removal—soot and deposits–-but also part of the stone substrate. Roughness results were complemented with scanning electron microscopy observations and analyses and colour measurements. Finally, it was possible to select the best cleaning method among the six that were analysed, for different areas and different stone materials. Therefore, this study confirms the measurement of surface roughness as a reliable test to determine the suitability of stone cleaning methods; it is a non-destructive technique, portable and friendly to use, which can help us to rapidly assess—together with other techniques—the efficacy and aggressiveness of the stone cleaning method. (paper)

  5. Large area optical mapping of surface contact angle.

    Science.gov (United States)

    Dutra, Guilherme; Canning, John; Padden, Whayne; Martelli, Cicero; Dligatch, Svetlana

    2017-09-04

    Top-down contact angle measurements have been validated and confirmed to be as good if not more reliable than side-based measurements. A range of samples, including industrially relevant materials for roofing and printing, has been compared. Using the top-down approach, mapping in both 1-D and 2-D has been demonstrated. The method was applied to study the change in contact angle as a function of change in silver (Ag) nanoparticle size controlled by thermal evaporation. Large area mapping reveals good uniformity for commercial Aspen paper coated with black laser printer ink. A demonstration of the forensic and chemical analysis potential in 2-D is shown by uncovering the hidden CsF initials made with mineral oil on the coated Aspen paper. The method promises to revolutionize nanoscale characterization and industrial monitoring as well as chemical analyses by allowing rapid contact angle measurements over large areas or large numbers of samples in ways and times that have not been possible before.

  6. Trace element composition and distribution in micron area of dinosaur eggshell fossils determined by proton microprobe

    International Nuclear Information System (INIS)

    Chen Youhong; Zhu Jieqing; Wang Xiaohong; Wang Yimin

    1997-01-01

    The scanning proton microprobe and micro-PIXE quantitative analysis technique have been used to determine composition and distribution of the trace elements in micron areas of dinosaur eggshell fossils from the stratum of Upper Cretaceous system at Nanxiong Basin in Guangdong Province, China. The study shows that the trace elements mainly include Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Sb, Ba and Pb in the micron area, but they present different distributions. While the elements Sr is mainly enriched in the near surface layer, others mainly reside in the near inner layer. A preliminary discussion on the reason of the dinosaur extinction is given based on the above study

  7. Trace element composition and distribution in micron area of dinosaur eggshell fossils determined by proton microprobe

    International Nuclear Information System (INIS)

    Chen Youhong; Zhu Jieqing; Wang Xiaohong; Wang Yimin

    1997-01-01

    The scanning proton microprobe and micro-PIXE quantitative analysis technique have been used to determine composition and distribution of the trace elements in micron areas of dinosaur eggshell fossils from the stratum of Upper Cretaceous system at Nanxiong Basin in Guangdong Province, China. The study shows that the trace elements mainly include Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Sb, Ba and Pb in the micron area, but they present different distributions. While the element Sr is mainly enriched in the near surface layer, others mainly reside in the near inner layer. A preliminary discussion on the reason of the dinosaur extinction is given based on the above study

  8. BLM National Surface Management Agency: Area Polygons, Withdrawal Area Polygons, and Special Public Purpose Withdrawal Area Polygons

    Data.gov (United States)

    Federal Geographic Data Committee — The SMA implementation is comprised of one feature dataset, with several polygon feature classes, rather than a single feature class. SurfaceManagementAgency: The...

  9. Cyclic Brunn-Minkowski Inequalities for p -affine surface area | Zhao ...

    African Journals Online (AJOL)

    In 2010, Werner and Ye extended the denition for mixed p-affine surface area to all real numbers p. Following this, we establish some isoperimetric inequalities for the general mixed p-affine surface area. The results in special cases yield some of the recent results on inequalities of this type. Mathematics Subject ...

  10. 30 CFR 933.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE NORTH CAROLINA § 933.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated Unsuitable for Coal Mining by Act of Congress, with the exception of §§ 761.11(c) and 761.12(f)(1), shall apply to surface coal mining and reclamation...

  11. The Effect of Specific Surface Area of Chitin-Metal Silicate Coprocessed Excipient on the Chemical Decomposition of Cefotaxime Sodium.

    Science.gov (United States)

    Al-Nimry, Suhair S; Alkhamis, Khouloud A; Alzarieni, Kawthar Z

    2017-02-01

    Chitin-metal silicates are multifunctional excipients used in tablets. Previously, a correlation between the surface acidity of chitin-calcium and chitin-magnesium silicate and the chemical decomposition of cefotaxime sodium was found but not with chitin-aluminum silicate. This lack of correlation could be due to the catalytic effect of silica alumina or the difference in surface area of the excipients. The objective of this study was to investigate the effect of the specific surface area of the excipient on the chemical decomposition of cefotaxime sodium in the solid state. Chitin was purified and coprocessed with different metal silicates to prepare the excipients. The specific surface area was determined using gas adsorption. The chemical decomposition was studied at constant temperature and relative humidity. Also, the degradation in solution was studied. A correlation was found between the degradation rate constant and the surface area of chitin-aluminum and chitin-calcium silicate but not with chitin-magnesium silicate. This was due to the small average pore diameter of this excipient. Also, the degradation in solution was slower than in solid state. In conclusion, the stability of cefotaxime sodium was dependent on the surface area of the excipient in contact with the drug. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  12. Surface and subsurface conditions in permafrost areas - a literature review

    International Nuclear Information System (INIS)

    Vidstrand, Patrik

    2003-02-01

    This report contains a summary of some of the information within existing technical and scientific literature on permafrost. Permafrost is viewed as one of the future climate driven process domains that may exist in Scandinavia, and that may give rise to significantly different surface and subsurface conditions than the present. Except for changes in the biosphere, permafrost may impact hydraulic, mechanical, and chemical subsurface processes and conditions. Permafrost and its influences on the subsurface conditions are thus of interest for the performance and safety assessments of deep geological waste repositories. The definition of permafrost is 'ground that stays at or below 0 deg C for at least two consecutive years'. Permafrost will effect the geological subsurface to some depth. How deep the permafrost may grow is a function of the heat balance, thermal conditions at the surface and within the ground, and the geothermal heat flux from the Earth's inner parts. The main chapters of the report summaries the knowledge on permafrost evolution, occurrence and distribution, and extracts information concerning hydrology and mechanical and chemical impacts due to permafrost related conditions. The results of a literature review are always dependent on the available literature. Concerning permafrost there is some literature available from investigations in the field of long-term repositories and some from mining industries. However, reports of these investigations are few and the bulk of permafrost literature comes from the science departments concerned with surficial processes (e.g. geomorphology, hydrology, agriculture, etc) and from engineering concerns, such as foundation of constructions and pipeline design. This focus within the permafrost research inevitably yields a biased but also an abundant amount of information on localised surficial processes and a limited amount on regional and deep permafrost characteristics. Possible conclusions are that there is

  13. Surface and subsurface conditions in permafrost areas - a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Vidstrand, Patrik [Bergab, Goeteborg (Sweden)

    2003-02-01

    This report contains a summary of some of the information within existing technical and scientific literature on permafrost. Permafrost is viewed as one of the future climate driven process domains that may exist in Scandinavia, and that may give rise to significantly different surface and subsurface conditions than the present. Except for changes in the biosphere, permafrost may impact hydraulic, mechanical, and chemical subsurface processes and conditions. Permafrost and its influences on the subsurface conditions are thus of interest for the performance and safety assessments of deep geological waste repositories. The definition of permafrost is 'ground that stays at or below 0 deg C for at least two consecutive years'. Permafrost will effect the geological subsurface to some depth. How deep the permafrost may grow is a function of the heat balance, thermal conditions at the surface and within the ground, and the geothermal heat flux from the Earth's inner parts. The main chapters of the report summaries the knowledge on permafrost evolution, occurrence and distribution, and extracts information concerning hydrology and mechanical and chemical impacts due to permafrost related conditions. The results of a literature review are always dependent on the available literature. Concerning permafrost there is some literature available from investigations in the field of long-term repositories and some from mining industries. However, reports of these investigations are few and the bulk of permafrost literature comes from the science departments concerned with surficial processes (e.g. geomorphology, hydrology, agriculture, etc) and from engineering concerns, such as foundation of constructions and pipeline design. This focus within the permafrost research inevitably yields a biased but also an abundant amount of information on localised surficial processes and a limited amount on regional and deep permafrost characteristics. Possible conclusions are that

  14. The protection of urban areas from surface wastewater pollutions

    Directory of Open Access Journals (Sweden)

    Vialkova Elena

    2017-01-01

    Full Text Available In this paper it considered the problem of collection, treatment and discharge into waters of rain and melted wastewater. To reduce the load on the combined sewer system, there are engineering solutions collect rain and melt water for use in the irrigation of lawns and green spaces. Research carried out at the department “Water supply and sanitation”, (Russia, confirm the high pollution concentrations of meltwater and rainfall in urban arias. Series of measurements of heavy metal in rainwater runoff carried out in Hungary demonstrates clearly the differences in concentrations in the function of distance from the edge of the road. Also differences are introduced between pollution concentrations in runoff water from within and outside urban traffic roads. The quality of snow cover, forming meltwater is observed to be changing in dependence on roadway location. Quality characteristics of surface runoff and its sediments can be effectively improved with super-high frequency radiation (SHF treatment which is presented in this paper.

  15. The increase of surface area of a Brazilian palygorskite clay activated with sulfuric acid solutions using a factorial design

    Directory of Open Access Journals (Sweden)

    R. N. Oliveira

    2013-01-01

    Full Text Available Palygorskite is fibrous clay in which the structural tetrahedral and octahedral layers are organized in a way that structural channels are formed, leading to high surface area. However, impurities inside the channels and aggregated ones considerably reduce the available area. In order to increase the surface area, an activation treatment can be considered useful. The goal of this work is the activation of palygorskite from Guadalupe, Piauí, via sulfuric acid treatment using a two-level factorial design. The influence of three parameters (solution molarity, temperature and time on BET surface area was determined. Moreover, samples were characterized via X-ray diffraction (XRD and fluorescence (XRF, Fourier-transform infrared spectroscopy (FTIR and transmission electron microscopy (TEM. The largest surface area (282 m²/g without considerable changes in clay structure and morphology was found in a sample treated with 5M H2SO4 at 70°C for 1h. The main parameters that favored the improvement of the surface area were the solution's molarity, temperature and their interaction.

  16. 30 CFR 905.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 905.764 Section 905.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE CALIFORNIA § 905.764 Process for designating areas unsuitable for surface coal mining... coal mining operations beginning one year after the effective date of this program. ...

  17. 30 CFR 947.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 947.764 Section 947.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE WASHINGTON § 947.764 Process for designating areas unsuitable for surface coal mining... coal mining and reclamation operations. (b) The Secretary shall notify the Washington Department of...

  18. 30 CFR 903.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 903.764 Section 903.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE ARIZONA § 903.764 Process for designating areas unsuitable for surface coal mining... coal mining operations beginning June 24, 1996, one year after the effective date of this program. ...

  19. Determinants of Solid Waste Disposal Practices in Urban Areas of ...

    African Journals Online (AJOL)

    Waste management is a growing public concern in Ethiopia. This study examined the patterns and determinants of solid waste disposal practices adopted by families using a random sample of 200 households from Jimma town. The descriptive results revealed that open-dumping, burying, burning and composting are the ...

  20. Determination of Cross-Sectional Area of Focused Picosecond Gaussian Laser Beam

    Science.gov (United States)

    Ledesma, Rodolfo; Fitz-Gerald, James; Palmieri, Frank; Connell, John

    2018-01-01

    Measurement of the waist diameter of a focused Gaussian-beam at the 1/e(sup 2) intensity, also referred to as spot size, is key to determining the fluence in laser processing experiments. Spot size measurements are also helpful to calculate the threshold energy and threshold fluence of a given material. This work reports an application of a conventional method, by analyzing single laser ablated spots for different laser pulse energies, to determine the cross-sectional area of a focused Gaussian-beam, which has a nominal pulse width of approx. 10 ps. Polished tungsten was used as the target material, due to its low surface roughness and low ablation threshold, to measure the beam waist diameter. From the ablative spot measurements, the ablation threshold fluence of the tungsten substrate was also calculated.

  1. Improved capacity to evaluate changes in intestinal mucosal surface area using mathematical modeling.

    Science.gov (United States)

    Greig, Chasen J; Cowles, Robert A

    2017-07-01

    Quantification of intestinal mucosal growth typically relies on morphometric parameters, commonly villus height, as a surrogate for presumed changes in mucosal surface area (MSA). We hypothesized that using mathematical modeling based on multiple unique measurements would improve discrimination of the effects of interventions on MSA compared to standard measures. To determine the ability of mathematical modeling to resolve differences in MSA, a mouse model with enhanced serotonin (5HT) signaling known to stimulate mucosal growth was used. 5-HT signaling is potentiated by targeting the serotonin reuptake transporter (SERT) molecule. Selective serotonin reuptake inhibitor-treated wild-type (WT-SSRI), SERT-knockout (SERTKO), and wild-type C57Bl/6 (WT) mice were used. Distal ileal sections were H&E-stained. Villus height (VH), width (VW), crypt width (CW), and bowel diameter were used to calculate surface area enlargement factor (SEF) and MSA. VH alone for SERTKO and SSRI was significantly increased compared to WT, without a difference between SERTKO and WT-SSRI. VW and CW were significantly decreased for both SERTKO and WT-SSRI compared to WT, and VW for WT-SSRI was also decreased compared to SERTKO. These changes increased SEF and MSA for SERTKO and WT-SSRI compared to WT. Additionally, SEF and MSA were significantly increased for WT-SSRI compared to SERTKO. Mathematical modeling provides a valuable tool for differentiating changes in intestinal MSA. This more comprehensive assessment of surface area does not appear to correlate linearly with standard morphometric measures and represents a more comprehensive method for discriminating between therapies aimed at increasing functional intestinal mucosa. © 2017 Wiley Periodicals, Inc.

  2. A large area experiment to determine cosmic ray isotopic abundances

    Science.gov (United States)

    Mauger, B. G.; Balasubrahmanyan, V. K.; Ormes, J. F.; Streitmatter, R. E.; Heinrich, W.; Simon, M.; Tittel, H. O.

    1983-01-01

    Measurements of the isotopic composition of cosmic rays have shown that the cosmic ray isotope ratios, Ne-22/Ne-20 and (Mg-25 + Mg-26)/Mg-24, exceed the solar abundance ratios by factors of 2.7 and 1.8, respectively. There are several processes which could be responsible for the observed excess of neutron-rich isotopes. The considered models imply neutron enrichment in the case of other, less abundant species, and a measurement of the involved isotopic abundances could provide a basis for the determination of the dominating processes occurring in cosmic ray sources. However, an experiment utilizing special equipment is necessary to conduct the required measurements. Such an experiment, the Aluminum Isotopic Composition Experiment (Alice), is being designed in a joint effort involving NASA and a West German university. Alice uses a Cherenkov-range technique to determine the isotopic composition of elements from oxygen through argon.

  3. Determinants of Household Food Security in Urban Areas

    Directory of Open Access Journals (Sweden)

    Sarah Ayu Mutiah

    2017-03-01

    Full Text Available Food security at household level is a very important precondition to foster the national and regional food security. Many people migrate to urban areas in the hope of improving their welfare. Generally people think that in the city there are more opportunities, but the opposite is true. The problem is more complex in the city especially for people who do not have adequate skills and education. This study aims to address whether  age of household head, household size, education level of household head, income, and distribution of subsidized rice policy affect the food security of urban poor households in Purbalingga district. A hundred respondents were selected from four top villages in urban areas of Purbalingga with the highest level of poverty. Using binary logistic regression, this study finds significant positive effect of education of household head and household income and significant negative effect of household size and raskin on household food security, while age of household head has no significant effect on household food security. The results imply the need for increased awareness of family planning, education, improved skills, and increased control of the implementation of subsidized rice for the poor.

  4. Changes in the Surface Area of Glaciers in Northern Eurasia

    Science.gov (United States)

    Khromova, T.; Nosenko, G.

    2012-12-01

    Glaciers are widely recognized as key indicators of climate change. Recent evidence suggests an acceleration of glacier mass loss in several key mountain regions. Glacier recession implies the landscape changes in the glacial zone, origin of new lakes and activation of natural disaster processes, catastrophic mudflows, ice avalanches, outburst floods, and etc. The presence of glaciers in itself threats to human life, economic activity and growing infrastructure. Economical and recreational human activity in mountain regions requires relevant information on snow and ice objects. Absence or inadequacy of such information results in financial and human losses. A more comprehensive evaluation of glacier changes is imperative to assess ice contributions to global sea level rise and the future of water resources from glacial basins. One of the urgent steps is a full inventory of all ice bodies, their volume and changes The first estimation of glaciers state and glaciers distribution in the big part of Northern Eurasia has been done in the USSR Glacier Inventory published in 1966 -1980 as a part of IHD activity. The Inventory is based on topographic maps and air photos and reflects the status of the glaciers in 1957-1970y. There is information about 23796 glaciers with area of 78222.3 km2 in the Inventory. It covers 23 glacier systems on Northern Eurasia. In the 80th the USSR Glacier Inventory has been transformed in the digital form as a part of the World Glacier Inventory. Recent satellite data provide a unique opportunity to look again at these glaciers and to evaluate changes in glacier extent for the second part of XX century. In the paper we report about 15 000 glaciers outlines for Caucasus, Pamir, Tien-Shan, Altai, Syntar-Khayata, Cherskogo Range, Kamchatka and Russian Arctic which have been derived from ASTER and Landsat imagery and could be used for glacier changes evaluation. The results show that glaciers are retreating in all these regions. There is, however

  5. Determining effective roadway design treatments for transitioning from rural areas to urban areas on state highways.

    Science.gov (United States)

    2008-09-01

    This report reviews an Oregon research effort to identify ways to calm operating speeds as the vehicles transition into developed suburban/urban areas from rural roads. Drivers of vehicles approaching the urban environment have few visual cues to red...

  6. Limits determination of microbial contamination present on surfaces from a pharmaceutical microbiology district reference laboratory

    Directory of Open Access Journals (Sweden)

    Natalia Charry

    2016-06-01

    Full Text Available Context: The bioburden present on the pharmaceutical microbiology laboratory’s surfaces, may increase the risk of cross-contamination when analytical tests are being carried out; periodic monitoring allows to set limits that reduce the risk. Aims: To determinate the limits of bioburden present on seven surfaces of the pharmaceutical microbiology laboratory, after the cleaning and disinfection process. Methods: The swabbing method was used for sampling. With a 25 cm2 stencil and a sterile swab, a sample was taken, passing the swab over five points of every surface chosen. A total aerobic microbial count and a total yeast and mold count was done. Finally, the average and the standard deviation of the counts was obtained. Results: The average from the counts obtained on each surface selected for the study, were below the recommended limits by international entities like the World Health Organization and the European Union, between others; also, the results generated in this study, allow to classify the biosafety cabinet as an ISO 5 area and the other areas as ISO 7. Conclusions: Bioburden levels on the tested surfaces are considered low, reducing the risk of cross-contamination, which could have a negative impact on laboratory’s activities. Also, it follows that disinfectant concentration used, is effectively.

  7. Permeability surface area product analysis in malignant brain edema prediction - A pilot study.

    Science.gov (United States)

    Volny, O; Cimflova, P; Lee, T-Y; Menon, B K; d'Esterre, C D

    2017-05-15

    Using an extended CT perfusion acquisition (150s), we sought to determine the association between perfusion parameters and malignant edema after ischemic stroke. Patients (from prospective study PROVE-IT, NCT02184936) with terminal internal carotid artery±proximal middle cerebral occlusion were involved. CTA was assessed for clot location and status of leptomeningeal collaterals. The following CTP parameters were calculated within the ischemic territory and contralaterally: permeability surface area product (PS), cerebral blood flow (CBF) and cerebral blood volume (CBV). PS was calculated using the adiabatic approximation to the Johnson and Wilson model. Outcome was evaluated by midline shift and infarction volume on follow-up imaging. Of 200 patients enrolled, 7 patients (3.5%) had midline shift≥5mm (2 excluded for poor-quality scans). Five patients with midline shift and 5 matched controls were analysed. There was no significant difference in mean PS, CBF and CBV within the ischemic territory between the two groups. A CBV threshold of 1.7ml/100g had the highest AUC=0.72, 95% CI=0.54-0.90 for early midline shift prediction, sensitivity and specificity were 0.83 and 0.67 respectively. Our preliminary results did not show significant differences in permeability surface area analysis if analysed for complete ischemic region. CBV parameter had the highest accuracy and there was a trend for the mean PS values for midline shift prediction. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Non-activated high surface area expanded graphite oxide for supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Vermisoglou, E.C.; Giannakopoulou, T.; Romanos, G.E.; Boukos, N.; Giannouri, M. [Institute of Nanoscience and Nanotechnology “Demokritos”, 153 43 Ag. Paraskevi, Attikis (Greece); Lei, C.; Lekakou, C. [Division of Mechanical, Medical, and Aerospace Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH (United Kingdom); Trapalis, C., E-mail: c.trapalis@inn.demokritos.gr [Institute of Nanoscience and Nanotechnology “Demokritos”, 153 43 Ag. Paraskevi, Attikis (Greece)

    2015-12-15

    Graphical abstract: - Highlights: • One-step exfoliation and reduction of graphite oxide via microwave irradiation. • Effect of pristine graphite (type, flake size) on the microwave expanded material. • Effect of pretreatment and oxidation cycles on the produced expanded material. • Expanded graphene materials with high BET surface areas (940 m{sup 2}/g–2490 m{sup 2}/g). • Non-activated graphene based materials suitable for supercapacitors. - Abstract: Microwave irradiation of graphite oxide constitutes a facile route toward production of reduced graphene oxide, since during this treatment both exfoliation and reduction of graphite oxide occurs. In this work, the effect of pristine graphite (type, size of flakes), pretreatment and oxidation cycles on the finally produced expanded material was examined. All the types of graphite that were tested afforded materials with high BET surface areas ranging from 940 m{sup 2}/g to 2490 m{sup 2}/g, without intervening an activation stage at elevated temperature. SEM and TEM images displayed exfoliated structures, where the flakes were significantly detached and curved. The quality of the reduced graphene oxide sheets was evidenced both by X-ray photoelectron spectroscopy and Raman spectroscopy. The electrode material capacitance was determined via electrochemical impedance spectroscopy and cyclic voltammetry. The materials with PEDOT binder had better performance (∼97 F/g) at low operation rates while those with PVDF binder performed better (∼20 F/g) at higher rates, opening up perspectives for their application in supercapacitors.

  9. Development of cortical thickness and surface area in autism spectrum disorder

    Directory of Open Access Journals (Sweden)

    Vincent T. Mensen

    2017-01-01

    Full Text Available Autism spectrum disorder (ASD is a neurodevelopmental disorder often associated with changes in cortical volume. The constituents of cortical volume – cortical thickness and surface area – have separable developmental trajectories and are related to different neurobiological processes. However, little is known about the developmental trajectories of cortical thickness and surface area in ASD. In this magnetic resonance imaging (MRI study, we used an accelerated longitudinal design to investigate the cortical development in 90 individuals with ASD and 90 typically developing controls, aged 9 to 20 years. We quantified cortical measures using the FreeSurfer software package, and then used linear mixed model analyses to estimate the developmental trajectories for each cortical measure. Our primary finding was that the development of surface area follows a linear trajectory in ASD that differs from typically developing controls. In typical development, we found a decline in cortical surface area between the ages of 9 and 20 that was absent in ASD. We found this pattern in all regions where developmental trajectories for surface area differed between groups. When we applied a more stringent correction that takes the interdependency of measures into account, this effect on cortical surface area retained significance for left banks of superior temporal sulcus, postcentral area, and right supramarginal area. These areas have previously been implicated in ASD and are involved in the interpretation and processing of audiovisual social stimuli and distinction between self and others. Although some differences in cortical volume and thickness were found, none survived the more stringent correction for multiple testing. This study underscores the importance of distinguishing between cortical surface area and thickness in investigating cortical development, and suggests the development of cortical surface area is of importance to ASD.

  10. Characterization of the intragranular water regime within subsurface sediments: pore volume, surface area, and mass transfer limitations

    Science.gov (United States)

    Hay, Michael B.; Stoliker, Deborah L.; Davis, James A.; Zachara, John M.

    2011-01-01

    Although "intragranular" pore space within grain aggregates, grain fractures, and mineral surface coatings may contain a relatively small fraction of the total porosity within a porous medium, it often contains a significant fraction of the reactive surface area, and can thus strongly affect the transport of sorbing solutes. In this work, we demonstrate a batch experiment procedure using tritiated water as a high-resolution diffusive tracer to characterize the intragranular pore space. The method was tested using uranium-contaminated sediments from the vadose and capillary fringe zones beneath the former 300A process ponds at the Hanford site (Washington). Sediments were contacted with tracers in artificial groundwater, followed by a replacement of bulk solution with tracer-free groundwater and the monitoring of tracer release. From these data, intragranular pore volumes were calculated and mass transfer rates were quantified using a multirate first-order mass transfer model. Tritium-hydrogen exchange on surface hydroxyls was accounted for by conducting additional tracer experiments on sediment that was vacuum dried after reaction. The complementary ("wet" and "dry") techniques allowed for the simultaneous determination of intragranular porosity and surface area using tritium. The Hanford 300A samples exhibited intragranular pore volumes of ~1% of the solid volume and intragranular surface areas of ~20%–35% of the total surface area. Analogous experiments using bromide ion as a tracer yielded very different results, suggesting very little penetration of bromide into the intragranular porosity.

  11. Experimental Study on the Microstructure Evolution of Mixed Disposal Paste in Surface Subsidence Areas

    Directory of Open Access Journals (Sweden)

    Wei Sun

    2016-05-01

    Full Text Available The integrated disposal of surface subsidence pits and surface solid waste can be realized by backfilling a surface subsidence area with a paste made from the solid wastes of mines, such as tailings and waste rock. The microstructures of these wastes determine the macroscopic properties of a paste backfill. This paper presents an experimental study on the internal structure evolution of pasty fluid mixed with different waste rock concentrations (10%, 30%, and 50% and cement dosages (1% and 2% under damage. To this end, a real-time computed tomography (CT scan is conducted using medical CT and a small loading device. Results show that UCS (uniaxial compressive strength increases when the amount of cement increases. Given a constant amount of cement, UCS increases first and then decreases as waste rock content increases. UCS is maximized at 551 kPa when the waste rock content is 30%. The paste body is a typical medium used to investigate initial damage, which mainly consists of microholes, pores, and microcracks. The initial damages also exhibit a high degree of random inhomogeneity. After loading, cracks are initiated and expand gradually from the original damage location until the overall damages are generated. The mesostructure evolution model of the paste body is divided into six categories, and this mesostructure is reasonable when the waste rock content is 30%.

  12. Specific surface area of a crushed welded tuff before and after aqueous dissolution

    Science.gov (United States)

    Reddy, M.M.; Claassen, H.C.

    1994-01-01

    Specific surface areas were measured for several reference minerals (anorthoclase, labradorite and augite), welded tuff and stream sediments from Snowshoe Mountain, near Creede, Colorado. Crushed and sieved tuff had an unexpectedly small variation in specific surface area over a range of size fractions. Replicate surface area measurements of the largest and smallest tuff particle size fractions examined (1-0.3 mm and <0.212 mm) were 2.3 ?? 0.2 m2/g for each size fraction. Reference minerals prepared in the same way as the tuff had smaller specific surface areas than that of the tuff of the same size fraction. Higher than expected tuff specific surface areas appear to be due to porous matrix. Tuff, reacted in solutions with pH values from 2 to 6, had little change in specific surface area in comparison with unreacted tuff. Tuff, reacted with solutions having high acid concentrations (0.1 M hydrochloric acid or sulfuric-hydrofluoric acid), exhibited a marked increase in specific surface area compared to unreacted tuff. ?? 1994.

  13. Polybrominated diphenyl ethers in surface soils from e-waste recycling areas and industrial areas in South China: concentration levels, congener profile, and inventory.

    Science.gov (United States)

    Gao, Shutao; Hong, Jianwen; Yu, Zhiqiang; Wang, Jingzhi; Yang, Guoyi; Sheng, Guoying; Fu, Jiamo

    2011-12-01

    Polybrominated diphenyl ethers (PBDEs) were determined in 60 surface soils from two e-waste recycling sites (Qingyuan and Guiyu, China) and their surrounding areas to assess the extent and influence of PBDEs from e-waste recycling sites on the surrounding areas. A total of 32 surface soils from industrial areas in South China were also investigated for comparison. The mean concentrations of total PBDEs in the e-waste recycling sites of Guiyu and Qingyuan were 2,909 and 3,230 ng/g dry weight, respectively, whereas the PBDE concentrations decreased dramatically (1-2 orders of magnitude) with increasing distance from the recycling site, suggesting that the e-waste recycling activities were the major source of PBDEs in the surrounding areas. Decabromodiphenyl ethers accounted for 77.0 to 85.8% of total PBDEs in e-waste recycling areas, whereas it accounted for 90.2% in industrial areas. Principal component analysis showed that the major source of PBDEs in e-waste recycling areas were a combination of penta-, octa-, and deca-BDE commercial formulations, whereas deca-BDE commercial formulations were the major source of PBDE congeners in industrial areas. The inventories of PBDEs gave preliminary estimates of 6.22 tons and 13.4 tons for the e-waste recycling areas and industrial areas. The results suggested that significantly higher PBDEs in the e-waste recycling sites have already affected surrounding areas negatively within a relatively large distance. Because of the environmental persistence, bioaccumulation, and toxicity of PBDEs, improving the recycling techniques employed at such facilities and developing e-waste management policies are necessary. Copyright © 2011 SETAC.

  14. Description of climate, surface hydrology, and near-surface hydrogeology. Preliminary site description. Forsmark area - version 1.2

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Per-Olof [Artesia Grundvattenkonsult AB, Stockholm (Sweden); Werner, Kent [SWECO VIAK AB/Golder Associates AB, Stockholm (Sweden); Bosson, Emma; Berglund, Sten [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Juston, John [DBE Sweden, Uppsala (Sweden)

    2005-06-15

    conductive zones shown to exist in the upper bedrock. The sediment stratigraphy of lakes and wetlands is crucial for their function as discharge areas for groundwater. Low-permeable sediments will restrict the discharge and result in a relocation of the discharge to areas where such sediments are missing. Concerning the interactions between surface water and groundwater, it may also be noted that comparisons between measured lake water levels and groundwater levels below and around lakes indicate that the lakes in some cases may act as sources of groundwater recharge. Specifically, observations from Lake Bolundsfjaerden and Lake Eckarfjaerden show that such conditions were at hand during the dry summer of 2003. However, whether the observed water level relations correspond to significant water fluxes depends also on the hydrogeological properties of the lake sediments and the underlying Quaternary deposits. 'Old' water with high chloride content has been found below Lake Bolundsfjaerden, Lake Eckarfjaerden and Lake Gaellsbotraesket. These observations can either be interpreted as the result of a continuous discharge of deep water, or as evidence of more or less stagnant water below the lakes. Furthermore, the relations between the sea water level and the water levels in Lake Norra Bassaengen, Lake Bolundsfjaerden and Lake Lillfjaerden show that inflow of sea water can occur during periods of high sea water levels. The results from the hydrological GIS modelling support the assumptions and conclusions in the descriptive model. The flow model is highly sensitive to the topography, as this is the only parameter determining the flow pattern. Consequently, the simulated locations of recharge and discharge areas are strongly influenced by the local topography. In addition, the flat topography implies that small errors in the topographical model (the Digital Elevation Model, DEM) may have large effects on the modelled flow pattern. Ditches, diverted water courses and

  15. Effect of specific surface area of MWCNTS on surface roughness and delamination in drilling Epoxy/Glass Fabric Composite

    Science.gov (United States)

    Ponnuvel, S.; Ananth, M. Prem

    2018-03-01

    In this study the effect of specific surface area of the MWCNTs on the drilled hole qualities was investigated. Epoxy araldite LY556 with hardener HY951 and E-glass coarse plain weave fabric are used for the fabrication of reference material (specimen A). Multi-WalledCarbon Nanotubes (MWCNTs) with diameters fabrication of study materials, namely specimen B and specimen C respectively. In specimen B the epoxy resin was filled with MWCNTs having a specific surface area >500 m2 g‑1. MWCNTs in specimen C had a specific surface area >110 m2 g‑1. Drilling experiments were conducted on all the three specimens. Two dimensional delamination factor and the surface roughness of the inner wall of the drilled holes were investigated using Grey Relational Analysis (GRA) and Analysis of variance (ANOVA). Two dimensional delamination factor showed better performance from specimen B and specimen C in comparison with specimen A suggesting improvement in the bonding between epoxy and the glass fiber in the presence of MWCNTs. Similar observations were made for surface roughness of the inner wall of the drilled holes at 1250 rpm. Whereas the presence of MWCNTs (Specimen B and specimen C) produced poor surface finish at 500 rpm in comparison with specimen A. Variations in the hole quality characteristics between specimen B and specimen C was marginal with better observations in specimen C.

  16. Large-area electromagnetic enhancement by a resonant excitation of surface waves on a metallic surface with periodic subwavelength patterns.

    Science.gov (United States)

    Zhang, Xin; Liu, Haitao; Zhong, Ying

    2013-10-07

    We theoretically investigate the electromagnetic enhancement on a metallic surface patterned with periodic subwavelength structures. Fully-vectorial calculations show a large-area electromagnetic enhancement (LAEE) on the surface, which strongly contrasts with the previously reported "hot spots" that occur in specific tiny regions and which relieves the rigorous requirement of the nano-scale location of sample molecules. The LAEE allows for designing more practicable substrates for many enhanced-spectra applications. By building up microscopic models, the LAEE is shown due to a resonant excitation of surface waves that include both the surface plasmon polariton (SPP) and a quasi-cylindrical wave (QCW). The surface waves propagate on the substrate over a long distance and thus greatly enlarge the area of electromagnetic enhancement compared to the nano-sized hot spots caused by localized modes. Gain medium is introduced to further strengthen the large-area surface-wave resonance, with which an enhancement factor (EF) of electric-field intensity up to a few thousands is achieved.

  17. Comparison of 2 root surface area measurement methods: 3-dimensional laser scanning and cone-beam computed tomography

    International Nuclear Information System (INIS)

    Tasanapanont, Jintana; Apisariyakul, Janya; Wattanachai, Tanapan; Jotikasthira, Dhirawat; Sriwilas, Patiyut; Midtboe, Marit

    2017-01-01

    The aim of this study was to compare the use of 3-dimensional (3D) laser scanning and cone-beam computed tomography (CBCT) as methods of root surface measurement. Thirty teeth (15 maxillary first premolars and 15 mandibular first premolars) from 8 patients who required extractions for orthodontic treatment were selected. Before extraction, pre-treatment CBCT images of all the patients were recorded. First, a CBCT image was imported into simulation software (Mimics version 15.01; Materialise, Leuven, Belgium) and the root surface area of each tooth was calculated using 3-Matic (version 7.01, Materialise, Leuven, Belgium). After extraction, all the teeth were scanned and the root surface area of each extracted tooth was calculated. The root surface areas calculated using these 2 measurement methods were analyzed using the paired t-test (P<.05). Correlations between the 2 methods were determined by calculating the Pearson correlation coefficient. The intraclass correlation coefficient (ICC) was used to assess intraobserver reliability. The root surface area measurements (230.11±41.97 mm 2 ) obtained using CBCT were slightly greater than those (229.31±42.46 mm2) obtained using 3D laser scanning, but not significantly (P=.425). A high Pearson correlation coefficient was found between the CBCT and the 3D laser scanner measurements. The intraobserver ICC was 1.000 for 3D laser scanning and 0.990 for CBCT. This study presents a novel CBCT approach for measuring the root surface area; this technique can be used for estimating the root surface area of non-extracted teeth

  18. Comparison of 2 root surface area measurement methods: 3-dimensional laser scanning and cone-beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tasanapanont, Jintana; Apisariyakul, Janya; Wattanachai, Tanapan; Jotikasthira, Dhirawat [Dept. of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai (Thailand); Sriwilas, Patiyut [Dept. of Radiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok (Thailand); Midtboe, Marit [Dept. of Clinical Dentistry - Orthodontics, Faculty of Medicine and Dentistry, University of Bergen, Bergen (Norway)

    2017-06-15

    The aim of this study was to compare the use of 3-dimensional (3D) laser scanning and cone-beam computed tomography (CBCT) as methods of root surface measurement. Thirty teeth (15 maxillary first premolars and 15 mandibular first premolars) from 8 patients who required extractions for orthodontic treatment were selected. Before extraction, pre-treatment CBCT images of all the patients were recorded. First, a CBCT image was imported into simulation software (Mimics version 15.01; Materialise, Leuven, Belgium) and the root surface area of each tooth was calculated using 3-Matic (version 7.01, Materialise, Leuven, Belgium). After extraction, all the teeth were scanned and the root surface area of each extracted tooth was calculated. The root surface areas calculated using these 2 measurement methods were analyzed using the paired t-test (P<.05). Correlations between the 2 methods were determined by calculating the Pearson correlation coefficient. The intraclass correlation coefficient (ICC) was used to assess intraobserver reliability. The root surface area measurements (230.11±41.97 mm{sup 2}) obtained using CBCT were slightly greater than those (229.31±42.46 mm2) obtained using 3D laser scanning, but not significantly (P=.425). A high Pearson correlation coefficient was found between the CBCT and the 3D laser scanner measurements. The intraobserver ICC was 1.000 for 3D laser scanning and 0.990 for CBCT. This study presents a novel CBCT approach for measuring the root surface area; this technique can be used for estimating the root surface area of non-extracted teeth.

  19. A Standardized Method for Measuring Internal Lung Surface Area via Mouse Pneumonectomy and Prosthesis Implantation.

    Science.gov (United States)

    Liu, Zhe; Fu, Siling; Tang, Nan

    2017-07-26

    Pulmonary morphology, physiology, and respiratory functions change in both physiological and pathological conditions. Internal lung surface area (ISA), representing the gas-exchange capacity of the lung, is a critical criterion to assess respiratory function. However, observer bias can significantly influence measured values for lung morphological parameters. The protocol that we describe here minimizes variations during measurements of two morphological parameters used for ISA calculation: internal lung volume (ILV) and mean linear intercept (MLI). Using ISA as a morphometric and functional parameter to determine the outcome of alveolar regeneration in both pneumonectomy (PNX) and prosthesis implantation mouse models, we found that the increased ISA following PNX treatment was significantly blocked by implantation of a prosthesis into the thoracic cavity 1 . The ability to accurately quantify ISA is not only expected to improve the reliability and reproducibility of lung function studies in injured-induced alveolar regeneration models, but also to promote mechanistic discoveries of multiple pulmonary diseases.

  20. On the relationship between enamel band complexity and occlusal surface area in Equids (Mammalia, Perissodactyla

    Directory of Open Access Journals (Sweden)

    Nicholas A. Famoso

    2016-07-01

    Full Text Available Enamel patterns on the occlusal surfaces of equid teeth are asserted to have tribal-level differences. The most notable example compares the Equini and Hipparionini, where Equini have higher crowned teeth with less enamel-band complexity and less total occlusal enamel than Hipparionini. Whereas previous work has successfully quantified differences in enamel band shape by dividing the length of enamel band by the square root of the occlusal surface area (Occlusal Enamel Index, OEI, it was clear that OEI only partially removes the effect of body size. Because enamel band length scales allometrically, body size still has an influence on OEI, with larger individuals having relatively longer enamel bands than smaller individuals. Fractal dimensionality (D can be scaled to any level, so we have used it to quantify occlusal enamel complexity in a way that allows us to get at an accurate representation of the relationship between complexity and body size. To test the hypothesis of tribal-level complexity differences between Equini and Hipparionini, we digitally traced a sample of 98 teeth, one tooth per individual; 31 Hipparionini and 67 Equini. We restricted our sampling to the P3-M2 to reduce the effect of tooth position. After calculating the D of these teeth with the fractal box method which uses the number of boxes of various sizes to calculate the D of a line, we performed a t-test on the individual values of D for each specimen, comparing the means between the two tribes, and a phylogenetically informed generalized least squares regression (PGLS for each tribe with occlusal surface area as the independent variable and D as the dependent variable. The slopes of both PGLS analyses were compared using a t-test to determine if the same linear relationship existed between the two tribes. The t-test between tribes was significant (p < 0.0001, suggesting different D populations for each lineage. The PGLS for Hipparionini was a positive but not

  1. 20 CFR 654.13 - Determination of areas of substantial unemployment.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Determination of areas of substantial unemployment. 654.13 Section 654.13 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF... 10582 § 654.13 Determination of areas of substantial unemployment. An area of substantial unemployment...

  2. 18 CFR Appendix A to Part 2 - Guidance for Determining the Acceptable Construction Area for Replacements

    Science.gov (United States)

    2010-04-01

    ... AND INTERPRETATIONS Pt. 2, App. A Appendix A to Part 2—Guidance for Determining the Acceptable Construction Area for Replacements These guidelines shall be followed to determine what area may be used to construct the replacement facility. Specifically, they address what areas, in addition to the permanent...

  3. Determination of Surface Properties of Liquid Transition Metals

    International Nuclear Information System (INIS)

    Korkmaz, S. D.

    2008-01-01

    Certain surface properties of liquid simple metals are reported. Using the expression derived by Gosh and coworkers we investigated the surface entropy of liquid transition metals namely Fe, Co and Ni. We have also computed surface tensions of the metals concerned. The pair distribution functions are calculated from the solution of Ornstein-Zernike integral equation with Rogers-Young closure using the individual version of the electron-ion potential proposed by Fioalhais and coworkers which was originally developed for solid state. The predicted values of surface tension and surface entropy are in very good agreement with available experimental data. The present study results show that the expression derived by Gosh and coworkers is very useful for the surface entropy by using Fioalhais pseudopotential and Rogers-Young closure

  4. Mercury's Surface Magnetic Field Determined from Proton-Reflection Magnetometry

    Science.gov (United States)

    Winslow, Reka M.; Johnson, Catherine L.; Anderson, Brian J.; Gershman, Daniel J.; Raines, Jim M.; Lillis, Robert J.; Korth, Haje; Slavin, James A.; Solomon, Sean C.; Zurbuchen, Thomas H.; hide

    2014-01-01

    Solar wind protons observed by the MESSENGER spacecraft in orbit about Mercury exhibit signatures of precipitation loss to Mercury's surface. We apply proton-reflection magnetometry to sense Mercury's surface magnetic field intensity in the planet's northern and southern hemispheres. The results are consistent with a dipole field offset to the north and show that the technique may be used to resolve regional-scale fields at the surface. The proton loss cones indicate persistent ion precipitation to the surface in the northern magnetospheric cusp region and in the southern hemisphere at low nightside latitudes. The latter observation implies that most of the surface in Mercury's southern hemisphere is continuously bombarded by plasma, in contrast with the premise that the global magnetic field largely protects the planetary surface from the solar wind.

  5. Surface area analysis of dental implants using micro-computed tomography.

    Science.gov (United States)

    Schicho, Kurt; Kastner, Johann; Klingesberger, Roman; Seemann, Rudolf; Enislidis, Georg; Undt, Gerhard; Wanschitz, Felix; Figl, Michael; Wagner, Arne; Ewers, Rolf

    2007-08-01

    In this study, we present and evaluate a micro-computed tomography (micro-CT)-based method for the calculation of the potential bone/implant contact area (p-BICA) on the surface of dental implants. For seven commercially available implants (Ankylos implant, Brånemark System, Frialit CELLplus, Replace((R)) Select Tapered, Straumann Solid screw, XiVE S CELLplus, 3i Osseotite XP Threaded Miniplant, the p-BICA surface is determined by means of three-dimensional X-ray computed-tomography and computer-based data processing. Measurements were repeated two times, and the stability and repeatability of the measurement method were evaluated. Our analysis revealed a p-BICA of 118 mm(2) for the XiVE S CELLplus implant, 134 mm(2) for the Ankylos, 136 mm(2) for the Frialit CELLplus, 138 mm(2) for the Brånemark System, 139 mm(2) for the Replace((R)), 159 mm(2) for the 3i Osseotite XP and 199 mm(2) for the Straumann Solid screw implant. The measurement method proved to be stable and led to reproducible results. The micro- and macrostructure of dental implants define the surface and the p-BICA. Precise determination of this parameter can be achieved by means of the micro-CT-based method as presented in this study. The value of p-BICA lies in the predictability of industrial design before preclinical and clinical testing. Based on this method, dental implant properties become comparable even if geometrical details are not disclosed by the manufacturer.

  6. Comparative analysis of surface soil moisture retrieval using VSWI and TVDI in karst areas

    Science.gov (United States)

    Yan, Hongbo; Zhou, Guoqing; Lu, Xianjian

    2015-12-01

    Vegetation Supply Water Index (VSWI) and Temperature Vegetation dryness Index (TVDI) are two most commonly used methods for surface soil moisture (SSM) retrieval using electromagnetic spectrum of visible, near infrared and thermal infrared band. Both of them take into account the effect of vegetation index (VI) and surface temperature (Ts) on SSM. A comparative analysis of the ability and effect of the two methods for SSM retrieval in karst areas was carried out, using the remote sensing data of Landsat 8 OLI_TIRS. The study area is located in Guilin, which is a typical karst area. The experimental results show that TVDI is more suitable for SSM retrieval in karst areas.

  7. Ground Radiometric Method as a Tool for Determining the Surface Boundary of a Buried Bauxitic Karst

    Directory of Open Access Journals (Sweden)

    Kamal Kareem Ali

    2011-12-01

    Full Text Available Forty two ground radiometric measurements along nine traverses within a rectangular network area were taken across a bauxitic karst within the Ubaid Formation (Lower Jurassic in the Western Desert of Iraq. A 4-Channel Gamma Ray Spectrometer (GAD-6 with sodium iodide NaI (Tl crystal (GSP-4S was used in the field to measure the total radioactivity of the surface soil. Soil samples collected from the surface at each measurement point and core samples collected from a test well penetrating the karst were analyzed by Gamma ray spectrometer. The main objective of this study was to detect the hidden bauxitic karst and determine its surface boundary. The radioactivity on the surface of the karst was ranging between 60 and 80 count per second (c/s, while the background radioactivity of the Ubaid Formation, which hosts the karst, was ranging between 100 and150 c/s. Chemical weathering, especially dissolution and leaching moved uranium (238U and thorium(232Th from the overburden downward. Accordingly, these elements have been adsorbed on the surface of clay minerals and bauxite buried at a depth of about 5m causing enrichment with radioactivity. The leached overburden lack radioelements, so its radioactivity was less than background radioactivity level. The gamma ray spectroanalysis showed that the radioactivity of 238U and 232Th in the overburden was 0.5 and 3 Bq/Kg, whereas, in the bauxite and flint clay bed, it was 240 and 160 Bq/Kg respectively. Based on the radioactivity anomaly contrast on the surface, an isorad map was plotted and the karst diameter which represents low anomaly was determined to be ranging from 150 to 200m. The current study demonstrates that the ground radiometric method is quite useful for detecting the bauxitic karst and inferring its surface boundaries.

  8. CLPX-Satellite: EO-1 Hyperion Surface Reflectance, Snow-Covered Area, and Grain Size

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of apparent surface reflectance, subpixel snow-covered area and grain size collected from the Hyperion hyperspectral imager. The Hyperion...

  9. Ratio of Major Ions in Groundwater to Determine Saltwater Intrusion in Coastal Areas

    Science.gov (United States)

    Sudaryanto; Naily, Wilda

    2018-02-01

    Saltwater or seawater intrusion into groundwater aquifers occurs mostly in big cities and developing coastal cities. Coastal hydrology is associated with complex and highly dynamic environmental characteristics of interactions between groundwater, surface water, and water from the estuary. The rise of sea levels and excessive use of groundwater for clean water source trigger saltwater intrusion. Identification of saltwater intrusion into groundwater can be done by groundwater sampling and major ion analysis. The major ions dissolved in water are Ca, Mg, Na, K, Cl, HCO3, and SO4; the major ion ratios are Cl/Br, Ca/Mg, Ca/ (HCO3 and SO4), and Na/Cl. By knowing whether groundwater quality has been or has not been influenced by saltwater, groundwater zones can be determined in every coastal area. In addition, by analyzing and reviewing some concepts about the intrusion or contamination of saltwater into groundwater, there will be sufficient results for the identification of saltwater intrusion.

  10. Interdependence between body surface area and ultraviolet B dose in vitamin D production

    DEFF Research Database (Denmark)

    Bogh, M K B; Schmedes, Anne; Philipsen, P A

    2011-01-01

    Ultraviolet (UV) B radiation increases serum vitamin D level expressed as 25-hydroxyvitamin-D(3) [25(OH)D], but the relationship to body surface area and UVB dose needs investigation.......Ultraviolet (UV) B radiation increases serum vitamin D level expressed as 25-hydroxyvitamin-D(3) [25(OH)D], but the relationship to body surface area and UVB dose needs investigation....

  11. Estimation of surface area concentration of workplace incidental nanoparticles based on number and mass concentrations

    Science.gov (United States)

    Park, J. Y.; Ramachandran, G.; Raynor, P. C.; Kim, S. W.

    2011-10-01

    Surface area was estimated by three different methods using number and/or mass concentrations obtained from either two or three instruments that are commonly used in the field. The estimated surface area concentrations were compared with reference surface area concentrations (SAREF) calculated from the particle size distributions obtained from a scanning mobility particle sizer and an optical particle counter (OPC). The first estimation method (SAPSD) used particle size distribution measured by a condensation particle counter (CPC) and an OPC. The second method (SAINV1) used an inversion routine based on PM1.0, PM2.5, and number concentrations to reconstruct assumed lognormal size distributions by minimizing the difference between measurements and calculated values. The third method (SAINV2) utilized a simpler inversion method that used PM1.0 and number concentrations to construct a lognormal size distribution with an assumed value of geometric standard deviation. All estimated surface area concentrations were calculated from the reconstructed size distributions. These methods were evaluated using particle measurements obtained in a restaurant, an aluminum die-casting factory, and a diesel engine laboratory. SAPSD was 0.7-1.8 times higher and SAINV1 and SAINV2 were 2.2-8 times higher than SAREF in the restaurant and diesel engine laboratory. In the die casting facility, all estimated surface area concentrations were lower than SAREF. However, the estimated surface area concentration using all three methods had qualitatively similar exposure trends and rankings to those using SAREF within a workplace. This study suggests that surface area concentration estimation based on particle size distribution (SAPSD) is a more accurate and convenient method to estimate surface area concentrations than estimation methods using inversion routines and may be feasible to use for classifying exposure groups and identifying exposure trends.

  12. Estimation of surface area concentration of workplace incidental nanoparticles based on number and mass concentrations

    International Nuclear Information System (INIS)

    Park, J. Y.; Ramachandran, G.; Raynor, P. C.; Kim, S. W.

    2011-01-01

    Surface area was estimated by three different methods using number and/or mass concentrations obtained from either two or three instruments that are commonly used in the field. The estimated surface area concentrations were compared with reference surface area concentrations (SA REF ) calculated from the particle size distributions obtained from a scanning mobility particle sizer and an optical particle counter (OPC). The first estimation method (SA PSD ) used particle size distribution measured by a condensation particle counter (CPC) and an OPC. The second method (SA INV1 ) used an inversion routine based on PM1.0, PM2.5, and number concentrations to reconstruct assumed lognormal size distributions by minimizing the difference between measurements and calculated values. The third method (SA INV2 ) utilized a simpler inversion method that used PM1.0 and number concentrations to construct a lognormal size distribution with an assumed value of geometric standard deviation. All estimated surface area concentrations were calculated from the reconstructed size distributions. These methods were evaluated using particle measurements obtained in a restaurant, an aluminum die-casting factory, and a diesel engine laboratory. SA PSD was 0.7–1.8 times higher and SA INV1 and SA INV2 were 2.2–8 times higher than SA REF in the restaurant and diesel engine laboratory. In the die casting facility, all estimated surface area concentrations were lower than SA REF . However, the estimated surface area concentration using all three methods had qualitatively similar exposure trends and rankings to those using SA REF within a workplace. This study suggests that surface area concentration estimation based on particle size distribution (SA PSD ) is a more accurate and convenient method to estimate surface area concentrations than estimation methods using inversion routines and may be feasible to use for classifying exposure groups and identifying exposure trends.

  13. Changes in the intestinal microvillous surface area during reproduction and ageing in the female rat.

    OpenAIRE

    Pénzes, L; Regius, O

    1985-01-01

    A morphometric study has been undertaken of the changes that occur in the microvillous surface area of young, pregnant, lactating, old and senescent rats. It has been shown that the microvilli are organelles with a quite stable conformation and that they exhibit no large scale dimensional changes throughout almost the entire life span. Lactation, however, does induce an apparent increase in microvillous surface area which may be associated with the significant changes which occur to the struc...

  14. Relationship between specific surface area and spatial correlation functions for anisotropic porous media

    Energy Technology Data Exchange (ETDEWEB)

    Berryman, J.G.

    1987-01-01

    A result of Debye, Anderson, and Brumberger (P. Debye, H. R. Anderson, Jr., and H. Brumberger, J. Appl. Phys. 28, 679 (1957)) for isotropic porous media states that the derivative of the two-point spatial correlation at the origin is equal to minus one-quarter of the specific surface area. This result is generalized for nonisotropic media by noting that the angular average of the anisotropic two-point spatial correlation function has the same relationship to the specific surface area.

  15. Determining the Effect of Cutting Parameters on Surface Roughness ...

    African Journals Online (AJOL)

    The aim of present research focuses on the prediction of machining parameters that improve the quality of surface finish. The surface roughness is one of the important properties of work piece quality in the CNC (Computer Numerical Control) turning process. An effective approach of optimization techniques genetic ...

  16. Lake Chad Total Surface Water Area as Derived from Land Surface Temperature and Radar Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Frederick Policelli

    2018-02-01

    Full Text Available Lake Chad, located in the middle of the African Sahel belt, underwent dramatic decreases in the 1970s and 1980s leaving less than ten percent of its 1960s surface water extent as open water. In this paper, we present an extended record (dry seasons 1988–2016 of the total surface water area of the lake (including both open water and flooded vegetation derived using Land Surface Temperature (LST data (dry seasons 2000–2016 from the NASA Terra MODIS sensor and EUMETSAT Meteosat-based LST measurements (dry seasons 1988–2001 from an earlier study. We also examine the total surface water area for Lake Chad using radar data (dry seasons 2015–2016 from the ESA Sentinel-1a mission. For the limited number of radar data sets available to us (18 data sets, we find on average a close match between the estimates from these data and the corresponding estimates from LST, though we find spatial differences in the estimates using the two types of data. We use these spatial differences to adjust the record (dry seasons 2000–2016 from MODIS LST. Then we use the adjusted record to remove the bias of the existing LST record (dry seasons 1988–2001 derived from Meteosat measurements and combine the two records. From this composite, extended record, we plot the total surface water area of the lake for the dry seasons of 1988–1989 through 2016–2017. We find for the dry seasons of 1988–1989 to 2016–2017 that the maximum total surface water area of the lake was approximately 16,800 sq. km (February and May, 2000, the minimum total surface water area of the lake was approximately 6400 sq. km (November, 1990, and the average was approximately 12,700 sq. km. Further, we find the total surface water area of the lake to be highly variable during this period, with an average rate of increase of approximately 143 km2 per year.

  17. Geohydrology and susceptibility of major aquifers to surface contamination in Alabama, area 7

    Science.gov (United States)

    Mooty, W.S.

    1987-01-01

    The geohydrology and susceptibility of the seven major aquifers to surface contamination in Area 7 - Bibb, Dallas, Hale, Perry, and Wilcox Counties, are described. Aquifers in the northern part of the study area are in Paleozoic limestones and dolomite formations. Deposits in the central part of the study area are predominately of Cretaceous age and contain the Coker, Gordo, and Eutaw aquifers. Although the southern part of the study area has many deposits of Tertiary age, the Ripley Formation of Cretaceous age is the major aquifer. Contamination of any of the major aquifers is improbable because the majority of the recharge area for the primary aquifers is woodland, pasture, or farmland. Downdip from their outcrops, the major aquifers in the study area are protected from land surface contamination by relatively impermeable layers of clay and chalk. The aquifers that are highly susceptible to contamination are the ones in the limestone and dolomite formations in northern Bibb County. Sinkholes exist in the recharge area of these formations and could provide a direct link for contaminates from the land surface to the water table. An area northeast of the Selma well field is also highly susceptible to contamination. The Eutaw Formation in this area is overlain by alluvial deposits that could increase recharge to the aquifer by slowing the runoff rate of surface water. (USGS)

  18. Changes in Thickness and Surface Area of the Human Cortex and Their Relationship with Intelligence

    NARCIS (Netherlands)

    Schnack, Hugo G.; Van Haren, Neeltje E M; Brouwer, Rachel M.; Evans, Alan; Durston, Sarah; Boomsma, Dorret I.; Kahn, René S.; Hulshoff Pol, Hilleke E.

    2015-01-01

    Changes in cortical thickness over time have been related to intelligence, but whether changes in cortical surface area are related to general cognitive functioning is unknown. We therefore examined the relationship between intelligence quotient (IQ) and changes in cortical thickness and surface

  19. Greenland surface mass-balance observations from the ice-sheet ablation area and local glaciers

    DEFF Research Database (Denmark)

    Machguth, Horst; Thomsen, Henrik H.; Weidick, Anker

    2016-01-01

    Glacier surface mass-balance measurements on Greenland started more than a century ago, but no compilation exists of the observations from the ablation area of the ice sheet and local glaciers. Such data could be used in the evaluation of modelled surface mass balance, or to document changes in g...

  20. Greenland surface mass-balance observations from the ice-sheet ablation area and local glaciers

    NARCIS (Netherlands)

    Machguth, Horst; Thomsen, Henrik H.; Weidick, Anker; Ahlstrøm, Andreas P.; Abermann, Jakob; Andersen, Morten L.; Andersen, Signe B.; Bjørk, Anders A.; Box, Jason E.; Braithwaite, Roger J.; Bøggild, Carl E.; Citterio, Michele; Clement, Poul; Colgan, William; Fausto, Robert S.; Gleie, Karin; Gubler, Stefanie; Hasholt, Bent; Hynek, Bernhard; Knudsen, Niels T.; Larsen, Signe H.; Mernild, Sebastian H.; Oerlemans, Johannes; Oerter, Hans; Olesen, Ole B.; Smeets, C. J P Paul; Steffen, Konrad; Stober, Manfred; Sugiyama, Shin; Van As, Dirk; Van Den Broeke, Michiel R.; Van De Wal, Roderik S W

    2016-01-01

    Glacier surface mass-balance measurements on Greenland started more than a century ago, but no compilation exists of the observations from the ablation area of the ice sheet and local glaciers. Such data could be used in the evaluation of modelled surface mass balance, or to document changes in

  1. Models of bedrock surface and overburden thickness over Olkiluoto island and nearby sea area

    Energy Technology Data Exchange (ETDEWEB)

    Moenkkoenen, H. [WSP Finland Oy, Helsinki (Finland)

    2012-04-15

    In this report, a model of bedrock surface and a model of overburden thickness over the Olkiluoto Island and the nearby sea area are presented. Also in purpose to produce material for biosphere and radionuclide transport modelling, stratigraphy models of different sediment layers were created at two priority areas north and south of the Olkiluoto Island. The work concentrated on the collection and description of available data of bedrock surface and overburden thickness. Because the information on the bedrock surface and overburden is collected from different sources and is based on a number of types of data the quality and applicability of data sets varies. Consequently also the reliability in different parts of the models varies. Input data for the bedrock surface and overburden thickness models include 2928 single points and additional outcrops observations (611 polygons) in the modelled area. In addition, the input data include 173 seismic refraction lines (6534 points) and acousticseismic sounding lines (26655 points from which 13721 points are located in model area) in the Olkiluoto offshore area. The average elevation of bedrock surface in area is 2.1 metres above the sea level. The average thickness of overburden is 2.5 metres varying typically between 2 - 4 metres. Thickest overburden covers (approximately 16 metres) of terrestrial area are located at the western end of the Olkiluoto Island and in sea basin south of the island. (orig.)

  2. Surface area loss and increased sphericity account for the splenic entrapment of subpopulations of Plasmodium falciparum ring-infected erythrocytes.

    Directory of Open Access Journals (Sweden)

    Innocent Safeukui

    Full Text Available Ex vivo perfusion of human spleens revealed innate retention of numerous cultured Plasmodium falciparum ring-infected red blood cells (ring-iRBCs. Ring-iRBC retention was confirmed by a microsphiltration device, a microbead-based technology that mimics the mechanical filtering function of the human spleen. However, the cellular alterations underpinning this retention remain unclear. Here, we use ImageStream technology to analyze infected RBCs' morphology and cell dimensions before and after fractionation with microsphiltration. Compared to fresh normal RBCs, the mean cell membrane surface area loss of trophozoite-iRBCs, ring-iRBCs and uninfected co-cultured RBCs (uRBCs was 14.2% (range: 8.3-21.9%, 9.6% (7.3-12.2% and 3.7% (0-8.4, respectively. Microsphilters retained 100%, ∼50% and 4% of trophozoite-iRBCs, ring-iRBCs and uRBCs, respectively. Retained ring-iRBCs display reduced surface area values (estimated mean, range: 17%, 15-18%, similar to the previously shown threshold of surface-deficient RBCs retention in the human spleen (surface area loss: >18%. By contrast, ring-iRBCs that successfully traversed microsphilters had minimal surface area loss and normal sphericity, suggesting that these parameters are determinants of their retention. To confirm this hypothesis, fresh normal RBCs were exposed to lysophosphatidylcholine to induce a controlled loss of surface area. This resulted in a dose-dependent retention in microsphilters, with complete retention occurring for RBCs displaying >14% surface area loss. Taken together, these data demonstrate that surface area loss and resultant increased sphericity drive ring-iRBC retention in microsphilters, and contribute to splenic entrapment of a subpopulation of ring-iRBCs. These findings trigger more interest in malaria research fields, including modeling of infection kinetics, estimation of parasite load, and analysis of risk factors for severe clinical forms. The determination of the threshold of

  3. Characteristics of hazardous airborne dust around an Indian surface coal mining area.

    Science.gov (United States)

    Ghose, Mrinal K; Majee, S R

    2007-07-01

    Surface coal mining creates more air pollution problems with respect to dust than underground mining . An investigation was conducted to evaluate the characteristics of the airborne dust created by surface coal mining in the Jharia Coalfield. Work zone air quality monitoring was conducted at six locations, and ambient air quality monitoring was conducted at five locations, for a period of 1 year. Total suspended particulate matter (TSP) concentration was found to be as high as 3,723 microg/m(3), respirable particulate matter (PM10) 780 microg/m(3), and benzene soluble matter was up to 32% in TSP in work zone air. In ambient air, the average maximum level of TSP was 837 microg/m(3), PM10 170 microg/m(3) and benzene soluble matter was up to 30%. Particle size analysis of TSP revealed that they were more respirable in nature and the median diameter was around 20 microm. Work zone air was found to have higher levels of TSP, PM10 and benzene soluble materials than ambient air. Variations in weight percentages for different size particles are discussed on the basis of mining activities. Anionic concentration in TSP was also determined. This paper concludes that more stringent air quality standards should be adopted for coal mining areas and due consideration should be given on particle size distribution of the air-borne dust while designing control equipment.

  4. Estimation of cerebral surface area using vertical sectioning and magnetic resonance imaging: a stereological study.

    Science.gov (United States)

    Acer, Niyazi; Cankaya, Mehmet Niyazi; Işçi, Oznur; Baş, Orhan; Camurdanoğlu, Mehmet; Turgut, Mehmet

    2010-01-15

    Stereological techniques using isotropic uniform random and vertical uniform random sections have been used for surface area estimation. However, there are a few studies in which the surface area of the brain is estimated using the vertical section technique in a stereological approach. The objective of the current study was to apply the vertical section technique using cycloid test probes for estimation of cerebral surface area in magnetic resonance imaging (MRI). In this study, cerebral surface areas were estimated in a total of 13 young subjects (6 males, 7 females) who were free of any neurological symptoms and signs. The means (+/-S.D.) of the surface areas were 1619.92+/-140. 97 cm (2), 1625.69+/-147. 58 cm(2) and 1674.69+/-160. 60 cm(2) for 36, 18 and 12 vertical sections, respectively. The mean coefficient of error obtained by applying cycloid test lines that use a 2. 8-cm ratio of area associated with each cycloid was estimated at 0.05). In addition, the three models correlated well with each other. From these results, it is concluded that the vertical section technique is an unbiased, efficient and reliable method and is ideally suited to in vivo examination of MRI data for estimating the surface area of the brain. Hence, we suggest that estimation of surface area using MRI and stereology may be clinically relevant for assessing cortical atrophy as well as for investigating the structure and function of cerebral hemispheres. Copyright 2009 Elsevier B.V. All rights reserved.

  5. Application of stereological methods to estimate post-mortem brain surface area using 3T MRI

    DEFF Research Database (Denmark)

    Furlong, Carolyn; García-Fiñana, Marta; Puddephat, Michael

    2013-01-01

    The Cavalieri and Vertical Sections methods of design based stereology were applied in combination with 3 tesla (i.e. 3T) Magnetic Resonance Imaging (MRI) to estimate cortical and subcortical volume, area of the pial surface, area of the grey-white matter boundary, and thickness of the cerebral c...

  6. Application of satellite images analysis to assess the variability of the surface thermal heat island distribution in urban areas

    Directory of Open Access Journals (Sweden)

    Fudała Janina

    2018-01-01

    Full Text Available One of the elements of the urban plans for adapting to climate change is to identify the range the urban heat island (UHI. To a relatively rare ground station network air temperature, one of the possible methods to identify this phenomenon in cities is the analysis of satellite images, and in particular the thermal images surface cities in conjunction with the land-use structure. In the publication is presented the application of indirect methods of determining surface characteristics of heat island in the cities of Upper Silesia Agglomeration on the basis of the analysis of the thermal images from the satellite Landsat for the period 1986-2016. It presents ways to interpret these images depending on the needs of determination the areas sensitive to the impact of the (UHI and define the areas where adaptation actions to the climate change should be undertaken.

  7. Application of satellite images analysis to assess the variability of the surface thermal heat island distribution in urban areas

    Science.gov (United States)

    Fudała, Janina; Nádudvari, Ádám; Bronder, Joachim; Fudała, Marta

    2018-01-01

    One of the elements of the urban plans for adapting to climate change is to identify the range the urban heat island (UHI). To a relatively rare ground station network air temperature, one of the possible methods to identify this phenomenon in cities is the analysis of satellite images, and in particular the thermal images surface cities in conjunction with the land-use structure. In the publication is presented the application of indirect methods of determining surface characteristics of heat island in the cities of Upper Silesia Agglomeration on the basis of the analysis of the thermal images from the satellite Landsat for the period 1986-2016. It presents ways to interpret these images depending on the needs of determination the areas sensitive to the impact of the (UHI) and define the areas where adaptation actions to the climate change should be undertaken.

  8. Laboratory Determination of Thermal Protection System Materials Surface Catalytic Properties

    Science.gov (United States)

    2007-07-01

    Zalar, A., "Recombination of Neutral Hydrogen Atoms on AISI 304 Stainless Steel Surface," Applied Surface Science, Vol. 144-145, 1999, pp. 399-403. 57...and test environments. Typically, these fits contain only the temperature dependence of the loss probability, with no information on pressure or...generated in the MESOX test facility in the PROMES-CNRS laboratory on a variety of ceramic materials.47-50 The MESOX facility uses a flow tube

  9. Quantitative Magnetic Resonance Imaging of Brainstem Volumes, Plaques, and Surface Area in the Occipital Regions of Patients with Multiple Sclerosis

    International Nuclear Information System (INIS)

    Alper, F.; Kantarci, M.; Altunkaynak, E.; Varoglu, A. O.; Karaman, A.; Oral, E.; Okur, A.

    2006-01-01

    Purpose: To determine brainstem volumes, number of plaques, and surface areas in the occipital lobes of patients with relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), and to investigate whether there is any correlation between brainstem volume and the number/surface areas of plaque in the occipital lobes. Material and Methods: Magnetic resonance imaging was obtained on 14 relapsing-remitting (RR) and 13 secondary progressive (SP) MS patients and 26 female control subjects. The Cavalieri method was used by modern design stereology to measure brainstem volume. The point-counting grid was used to evaluate sclerotic plaque surface areas in the occipital lobe. The number of plaques in the imaging section was calculated. Results: Brainstem volumes for RR and SP with multiple sclerosis and control subjects were 3647 mm 3 , 3515 mm 3 , and 4517 mm 3 , respectively. Mean number of plaques in the right-left occipital lobe was found to be 2.7-3.4 in RR-MS and 5.2-2.8 in SP-MS. Mean plaque surface area in the right-left occipital lobe was determined to be 58.52-88.24 mm 2 in RR MS and 124.3-64.82 mm 2 in SP MS. Brainstem volumes were significantly reduced in both groups of patients with MS compared to controls ( P <0.01). Conclusion: Magnetic-resonance-estimated volume and surface area values in multiple sclerosis may facilitate our understanding of the clinical situation of patients and provide a simple index for evaluating therapeutic efficiency

  10. Large area window on vacuum chamber surface for neutron scattering instruments

    International Nuclear Information System (INIS)

    Itoh, Shinichi; Yokoo, Tetsuya; Ueno, Kenji; Suzuki, Junichi; Teraoku, Takuji; Tsuchiya, Masao

    2012-01-01

    The feasibility of a large area window using a thin aluminum plate on the surface of the vacuum chamber for neutron scattering instruments at a pulsed neutron source was investigated. In the prototype investigation for a window with an area of 1m×1.4m and a thickness of 1 mm, the measured pressure dependence of the displacement agreed well with a calculation using a nonlinear strain–stress curve up to the plastic deformation region. In addition, we confirmed the repetition test up to 2000 pressurization-and-release cycles, which is sufficient for the lifetime of the vacuum chamber for neutron scattering instruments. Based on these investigations, an actual model of the window to be mounted on the vacuum chamber of the High Resolution Chopper Spectrometer (HRC) at J-PARC was designed. By using a calculated stress distribution on the window, the clamping structure capable of balancing the tension in the window was determined. In a model with a structure identical to the actual window, we confirmed the repetition test over more than 7000 pressurization-and-release cycles, which shows a lifetime long enough for the actual usage of the vacuum chamber on the HRC.

  11. Large Differences between Glaciers 3D Surface Extents and 2D Planar Areas in Central Tianshan

    Directory of Open Access Journals (Sweden)

    Xianwei Wang

    2017-04-01

    Full Text Available Most glaciers in China lie in high mountainous environments and have relatively large surface slopes. Common analyses consider glaciers’ projected areas (2D Area in a two-dimensional plane, which are much smaller than glacier’s topographic surface extents (3D Area. The areal difference between 2D planar areas and 3D surface extents exceeds −5% when the glacier’s surface slope is larger than 18°. In this study, we establish a 3D model in the Muzart Glacier catchment using ASTER GDEM data. This model is used to quantify the areal difference between glaciers’ 2D planar areas and their 3D surface extents in various slope zones and elevation bands by using the second Chinese Glacier Inventory (CGI2. Finally, we analyze the 2D and 3D area shrinking rate between 2007 and 2013 in Central Tianshan using glaciers derived from Landsat images by an object-based classification approach. This approach shows an accuracy of 89% when it validates by comparison of glaciers derived from Landsat and high spatial resolution GeoEye images. The extracted glaciers in 2007 also have an agreement of 89% with CGI2 data in the Muzart Glacier catchment. The glaciers’ 3D area is 34.2% larger than their 2D area from CGI2 in the Muzart Glacier catchment and by 27.9% in the entire Central Tianshan. Most underestimation occurs in the elevation bands of 4000–5000 m above sea level (a.s.l.. The 3D glacier areas reduced by 30 and 115 km2 between 2007 and 2013 in the Muzart Glacier catchment and Central Tianshan, being 37.0% and 27.6% larger than their 2D areas reduction, respectively. The shrinking rates decrease with elevation increase.

  12. Greenland surface mass-balance observations from the ice-sheet ablation area and local glaciers

    DEFF Research Database (Denmark)

    Machguth, Horst; Thomsen, Henrik H.; Weidick, Anker

    2016-01-01

    Glacier surface mass-balance measurements on Greenland started more than a century ago, but no compilation exists of the observations from the ablation area of the ice sheet and local glaciers. Such data could be used in the evaluation of modelled surface mass balance, or to document changes...... in glacier melt independently from model output. Here, we present a comprehensive database of Greenland glacier surface mass-balance observations from the ablation area of the ice sheet and local glaciers. The database spans the 123 a from 1892 to 2015, contains a total of similar to 3000 measurements from......-term time series of which there are only two exceeding 20 a. We use the data to analyse uncertainties in point measurements of surface mass balance, as well as to estimate surface mass-balance profiles for most regions of Greenland....

  13. Planar spatial correlations, anisotropy, and specific surface area of stationary random porous media

    International Nuclear Information System (INIS)

    Berryman, J.G.

    1998-01-01

    An earlier result of the author showed that an anisotropic spatial correlation function of a random porous medium could be used to compute the specific surface area when it is stationary as well as anisotropic by first performing a three-dimensional radial average and then taking the first derivative with respect to lag at the origin. This result generalized the earlier result for isotropic porous media of Debye et al. [J. Appl. Phys. 28, 679 (1957)]. The present article provides more detailed information about the use of spatial correlation functions for anisotropic porous media and in particular shows that, for stationary anisotropic media, the specific surface area can be related to the derivative of the two-dimensional radial average of the correlation function measured from cross sections taken through the anisotropic medium. The main concept is first illustrated using a simple pedagogical example for an anisotropic distribution of spherical voids. Then, a general derivation of formulas relating the derivative of the planar correlation functions to surface integrals is presented. When the surface normal is uniformly distributed (as is the case for any distribution of spherical voids), our formulas can be used to relate a specific surface area to easily measurable quantities from any single cross section. When the surface normal is not distributed uniformly (as would be the case for an oriented distribution of ellipsoidal voids), our results show how to obtain valid estimates of specific surface area by averaging measurements on three orthogonal cross sections. One important general observation for porous media is that the surface area from nearly flat cracks may be underestimated from measurements on orthogonal cross sections if any of the cross sections happen to lie in the plane of the cracks. This result is illustrated by taking the very small aspect ratio (penny-shaped crack) limit of an oblate spheroid, but holds for other types of flat surfaces as well

  14. Pore scale heterogeneity in the mineral distribution and surface area of porous rocks

    Science.gov (United States)

    Lai, Peter; Moulton, Kevin; Krevor, Samuel

    2014-05-01

    There are long-standing challenges in characterizing reactive transport in porous media at scales larger than individual pores. This hampers the prediction of the field-scale impact of geochemical processes on fluid flow [1]. This is a source of uncertainty for carbon dioxide injection, which results in a reactive fluid-rock system, particularly in carbonate rock reservoirs. A potential cause is the inability of the continuum approach to incorporate the impact of heterogeneity in pore-scale reaction rates. This results in part from pore-scale heterogeneities in surface area of reactive minerals [2,3]. The objective of this study was to quantify heterogeneity in reactive surface and observe the extent of its non-normal character. In this study we describe our work in using micron-scale x-ray imaging and other spectroscopic techniques for the purpose of describing the statistical distribution of reactive surface area within a porous medium, and identifying specific mineral phases and their distribution in 3-dimensions. Using in-house image processing techniques and auxilary charactersation with thin section, electron microscope and spectroscopic techniques we quantified the surface area of each mineral phase in the x-ray CT images. This quantification was validated against nitrogen BET surface area and backscattered electron imaging measurements of the CT-imaged samples. Distributions in reactive surface area for each mineral phase were constructed by calculating surface areas in thousands of randomly selected subvolume images of the total sample, each normalized to the pore volume in that image. In all samples, there is little correlation between the reactive surface area fraction and the volumetric fraction of a mineral in a bulk rock. Berea sandstone was far less heterogeneous and has a characteristic pore size at which a surface area distribution may be used to quantify heterogeneity. In carbonates, heterogeneity is more complex and surface area must be

  15. Technology of surface wastewater purification, including high-rise construction areas

    Science.gov (United States)

    Tsyba, Anna; Skolubovich, Yury

    2018-03-01

    Despite on the improvements in the quality of high-rise construction areas and industrial wastewater treatment, the pollution of water bodies continues to increase. This is due to the organized and unorganized surface untreated sewage entry into the reservoirs. The qualitative analysis of some cities' surface sewage composition is carried out in the work. Based on the published literature review, the characteristic contamination present in surface wastewater was identified. The paper proposes a new technology for the treatment of surface sewage and presents the results of preliminary studies.

  16. Estimating surface fluxes over the north Tibetan Plateau area with ASTER imagery

    Directory of Open Access Journals (Sweden)

    Weiqiang Ma

    2009-01-01

    Full Text Available Surface fluxes are important boundary conditions for climatological modeling and Asian monsoon system. The recent availability of high-resolution, multi-band imagery from the ASTER (Advanced Space-borne Thermal Emission and Reflection radiometer sensor has enabled us to estimate surface fluxes to bridge the gap between local scale flux measurements using micrometeorological instruments and regional scale land-atmosphere exchanges of water and heat fluxes that are fundamental for the understanding of the water cycle in the Asian monsoon system. A parameterization method based on ASTER data and field observations has been proposed and tested for deriving surface albedo, surface temperature, Normalized Difference Vegetation Index (NDVI, Modified Soil Adjusted Vegetation Index (MSAVI, vegetation coverage, Leaf Area Index (LAI, net radiation flux, soil heat flux, sensible heat flux and latent heat flux over heterogeneous land surface in this paper. As a case study, the methodology was applied to the experimental area of the Coordinated Enhanced Observing Period (CEOP Asia-Australia Monsoon Project (CAMP on the Tibetan Plateau (CAMP/Tibet, located at the north Tibetan Plateau. The ASTER data of 24 July 2001, 29 November 2001 and 12 March 2002 was used in this paper for the case of summer, winter and spring. To validate the proposed methodology, the ground-measured surface variables (surface albedo and surface temperature and land surface heat fluxes (net radiation flux, soil heat flux, sensible heat flux and latent heat flux were compared to the ASTER derived values. The results show that the derived surface variables and land surface heat fluxes in three different months over the study area are in good accordance with the land surface status. Also, the estimated land surface variables and land surface heat fluxes are in good accordance with ground measurements, and all their absolute percentage difference (APD is less than 10% in the validation sites

  17. Screening hydroxyapatite for cadmium and lead immobilization in aqueous solution and contaminated soil: The role of surface area.

    Science.gov (United States)

    Li, Hongying; Guo, Xisheng; Ye, Xinxin

    2017-02-01

    Hydroxyapatite (HAP) has been widely used to immobilize many cationic metals in water and soils. The specific reason why an increase in the surface area of HAP enhances cadmium (Cd) uptake, but has no effect on lead (Pb) uptake, is not clear. The aim of this study was to determine the factors causing the differences in sorption behavior between Cd and Pb by evaluating HAPs with different surface areas. We synthesized HAPs with two different surface areas, which were characterized by X-ray diffraction, N 2 adsorption, and scanning electron microscopy, and then evaluated them as sorbents for Cd and Pb removal by testing in single and binary systems. The sorption capacity of large surface area HAP (1.85mmol/g) for Cd in the single-metal system was higher than that of small surface area HAP (0.64mmol/g), but there were no differences between single- and binary-metal solutions containing Pb. After the Cd experiments, the HAP retained a stable structure and intact morphology, which promotes the accessibility of reactive sites for Cd. However, a newly formed precipitate covered the surface and blocked the channels in the presence of Pb, which reduced the number of potential adsorption sites on HAP for Cd and Pb. Remediation experiments using Cd- and Pb-contaminated soil produced similar results to the solution tests. These results indicate that alterations of the structure and morphology during the reaction is an important factor influencing metal sorption to HAP. Copyright © 2016. Published by Elsevier B.V.

  18. Satellite remotely-sensed land surface parameters and their climatic effects on urban areas

    Science.gov (United States)

    Zoran, M.; Savastru, R.; Savastru, D.; Ciobanu, M.; Tautan, M. N.; Miclos, S.

    2009-04-01

    Rapid urbanization transforms the natural landscape to anthropogenic urban land and changes surface biogeophysical characteristics.Urban growth affects the ecology of cities in a number of ways, such as eliminating and fragmenting native habitats, modifying local climate conditions, and generating anthropogenic pollutants.Urbanization has changed many landscapes throughout the world with serious ecological consequences.To understand the ecology of urban systems, it is necessary to quantify the spatial and temporal patterns of urbanization, which often requires dynamic modeling and spatial analysis. Geospatial information provided by satellite remote sensing sensors and biogeophysical field data are very useful for urban landuse-landcover dynamics and impacts analysis. The spatial and spectral variability of urban environments present fundamental challenges to deriving accurate remote sensing information for urban areas. By integrating high-resolution and medium-resolution satellite imagery with other geospatial information, have been investigated several land surface parameters including impervious surfaces and land surface temperatures for Bucharest metropolitan area in Romania. Percent impervious surface was used to quantitatively define the spatial extent and development density of urban land use. Land surface temperatures were retrieved by using a single band algorithm that processes both thermal infrared satellite data and total atmospheric water vapour content. Land surface temperatures have been analysed for different land use and land cover categories both in urban as well as in periurban areas. Because of the removal of vegetative cover and the reduction in evaporation over urban impervious surfaces, the urban heterogeneity of land surface and associated spatial extents influence surface thermal conditions. In situ meteorological data were integrated to assess regional climatic conditions. The spatial structure of surface heating influenced by landscape

  19. Response of three instruments devoted to surface-area for monodisperse and polydisperse aerosols in molecular and transition regimes

    Energy Technology Data Exchange (ETDEWEB)

    Bau, Sebastien; Witschger, Olivier [Institut National de Recherche et de Securite (INRS), Laboratoire de Metrologie des Aerosols, Rue du Morvan, CS 60027, 54519 Vandoeuvre Cedex (France); Gensdarmes, Francois [Institut de Radioprotection et de Surete Nucleaire (IRSN), Laboratoire de Physique et de Metrologie des Aerosols, BP 68, 91192 Gif-sur-Yvette (France); Thomas, Dominique, E-mail: sebastien.bau@inrs.fr [Laboratoire Reactions et Genie des Procedes (LRGP), groupe SAFE, 1 rue Grandville, BP 20041, 54001 Nancy Cedex (France)

    2011-07-06

    An increasing number of experimental and theoretical studies focus on airborne nanoparticles (NP) in relation with many aspects of risk assessment. Indeed, our understanding of the hazards, the actual exposures in the workplace and the limits of engineering controls and personal protective equipment with regard to NP are still under development. Several studies have already identified surface-area as an important determinant of low solubility nanoparticles toxicity. As a consequence, the concept that surface-area could be a relevant metric for characterizing exposure to low solubility airborne NP has been proposed [1]. To provide NP surface-area concentration, some direct-reading instruments have been designed, based on diffusion charging. The actual available instruments providing airborne NP surface-area concentration are studied in this work: LQ1-DC (Matter Engineering), AeroTrak{sup TM} 9000 (TSI) and NSAM (TSI model 3550). Their performances regarding monodisperse carbon NP have been investigated by Bau et al.. This work aims at completing the instruments characterization regarding monodisperse NP of other chemical composition (aluminium, copper, silver) and studying their performances against polydisperse aerosols of NP.

  20. Response of three instruments devoted to surface-area for monodisperse and polydisperse aerosols in molecular and transition regimes

    International Nuclear Information System (INIS)

    Bau, Sebastien; Witschger, Olivier; Gensdarmes, Francois; Thomas, Dominique

    2011-01-01

    An increasing number of experimental and theoretical studies focus on airborne nanoparticles (NP) in relation with many aspects of risk assessment. Indeed, our understanding of the hazards, the actual exposures in the workplace and the limits of engineering controls and personal protective equipment with regard to NP are still under development. Several studies have already identified surface-area as an important determinant of low solubility nanoparticles toxicity. As a consequence, the concept that surface-area could be a relevant metric for characterizing exposure to low solubility airborne NP has been proposed [1]. To provide NP surface-area concentration, some direct-reading instruments have been designed, based on diffusion charging. The actual available instruments providing airborne NP surface-area concentration are studied in this work: LQ1-DC (Matter Engineering), AeroTrak T M 9000 (TSI) and NSAM (TSI model 3550). Their performances regarding monodisperse carbon NP have been investigated by Bau et al.. This work aims at completing the instruments characterization regarding monodisperse NP of other chemical composition (aluminium, copper, silver) and studying their performances against polydisperse aerosols of NP.

  1. 10 CFR 100.11 - Determination of exclusion area, low population zone, and population center distance.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Determination of exclusion area, low population zone, and population center distance. 100.11 Section 100.11 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) REACTOR... and for Testing Reactors § 100.11 Determination of exclusion area, low population zone, and population...

  2. Pore scale heterogeneity in the mineral distribution and reactive surface area of rocks

    Science.gov (United States)

    Lai, P. E.; Krevor, S. C.

    2013-12-01

    There are long-standing challenges in characterizing reactive transport in porous media at scales larger than individual pores. This hampers the prediction of the field-scale impact of geochemical processes on fluid flow [1]. This is a source of uncertainty for CO2 injection, which results in a reactive fluid-rock system, particularly in carbonate rock reservoirs. A potential cause is the inability of the continuum approach to incorporate the impact of heterogeneity in pore-scale reaction rates. This results in part from pore-scale heterogeneities in surface area of reactive minerals [2,3]. In this study we have created μm resolution 3D images of 3 sandstone and 4 carbonate rocks using x-ray microtomography. Using in-house image processing techniques and auxiliary characterisation with thin section, electron microscope and spectroscopic techniques we quantified the surface area of each mineral phase in the x-ray CT images. This quantification was validated against N2 BET surface area and He porosity measurements of the imaged samples. Distributions in reactive surface area for each mineral phase were constructed by calculating surface areas in thousands of randomly selected subvolume images of the total sample, each normalized to the pore volume in that image. In all samples, there is little correlation between the reactive surface area fraction and the volumetric fraction of a mineral in a bulk rock. Berea sandstone was far less heterogeneous and has a characteristic pore size at which a surface area distribution may be used to quantify heterogeneity. In carbonates, heterogeneity is more complex and surface area must be characterized at multiple length scales for an accurate description of reactive transport. [1] Maher, Steefel, Depaolo and Vianni (2006) Geochimica et Cosmochimica Acta, 70, 337-363 [2] Landrot, Ajo-Franklin, Yang, Cabrini and Steefel (2012) Chemical Geology 318-319, 113-125 [3] Li, Peters and Celia (2007) American Journal of Science 307, 1146

  3. Determining the energetics of vicinal perovskite oxide surfaces

    NARCIS (Netherlands)

    Wessels, W.A.; Bollmann, Tjeerd Rogier Johannes; Koster, Gertjan; Zandvliet, Henricus J.W.; Rijnders, Augustinus J.H.M.

    2017-01-01

    The energetics of vicinal SrTiO3(001) and DyScO3(110), prototypical perovskite vicinal surfaces, has been studied using topographic atomic force microscopy imaging. The kink formation and strain relaxation energies are extracted from a statistical analysis of the step meandering. Both perovskite

  4. Determination of antibiotic residues in manure, soil, and surface waters

    Science.gov (United States)

    Christian, T.; Schneider, R.J.; Farber, H.A.; Skutlarek, D.; Meyer, M.T.; Goldbach, H.E.

    2003-01-01

    In the last years more and more often detections of antimicrobially active compounds ("antibiotics") in surface waters have been reported. As a possible input pathway in most cases municipal sewage has been discussed. But as an input from the realm of agriculture is conceivable as well, in this study it should be investigated if an input can occur via the pathway application of liquid manure on fields with the subsequent mechanisms surface run-off/interflow, leaching, and drift. For this purpose a series of surface waters, soils, and liquid manures from North Rhine-Westphalia (Northwestern Germany) were sampled and analyzed for up to 29 compounds by HPLC-MS/MS. In each of the surface waters antibiotics could be detected. The highest concentrations were found in samples from spring (300 ng/L of erythromycin). Some of the substances detected (e.g., tylosin), as well as characteristics in the landscape suggest an input from agriculture in some particular cases. In the investigation of different liquid manure samples by a fast immunoassay method sulfadimidine could be detected in the range of 1...2 mg/kg. Soil that had been fertilized with this liquid manure showed a content of sulfadimidine extractable by accelerated solvent extraction (ASE) of 15 ??g/kg dry weight even 7 months after the application. This indicates the high stability of some antibiotics in manure and soil.

  5. The determination of turbulent structures in the atmospheric surface layer

    NARCIS (Netherlands)

    Schols, J.L.J.

    1984-01-01

    The turbulent flow in the atmospheric surface layer (ASL) contains turbulent structures, which are defined as spatially coherent, organized flow motions. 'Organized' means that characteristic patterns, observed at a point in space, occur almost simultaneously in more than one turbulence signal and

  6. Determination of lunar surface ages from crater frequency–size ...

    Indian Academy of Sciences (India)

    Crater size–frequency distribution is one of the powerful techniques to estimate the ages of planetary surfaces, especially from remote sensing studies. This has been applied to images of the Moon obtained from Clementine mission in 1994. Simple techniques of measurement of the diameter of the craters (in pixels) are ...

  7. Surface determinants of low density lipoprotein uptake by endothelial cells

    International Nuclear Information System (INIS)

    Goeroeg, P.; Pearson, J.D.

    1984-01-01

    The surface sialic acid content of aortic endothelial cells in vitro was substantially lower in sparse cultures than at confluence. Binding of LDL to endothelial cells did not change at different culture densities and was unaffected by brief pretreatment with neuraminidase to partially remove surface sialic acid residues. In contrast, internalisation of LDL declined by a factor of 3 between low density cell cultures and confluent monolayers; neuraminidase pretreatment increased LDL uptake and the effect was most marked (>10-fold) at confluence. Pretreatment with cationised ferritin, which removed most of the surface sialic acid residues as well as glycosaminoglycans, increased LDL internalisation by up to 20-fold, again with most effect on confluent monolayers. Thus LDL uptake is inversely correlated with sialic acid content. We conclude that changes in the surface density of sialic acid (and possibly other charged) residues significantly modulate endothelial LDL uptake, and suggest that focal increases in LDL accumulation during atherogenesis may be related to alterations in endothelial endocytic properties at sites of increased cell turnover or damage. (author)

  8. Application of response surface methodology for determining cutting ...

    Indian Academy of Sciences (India)

    by software Minitab (multiple linear regression and response surface methodology) in order to express the influence degree of the main cutting variables such as cutting speed, feed rate and depth of cut on cutting force components. These models would be helpful in selecting cutting variables for optimization of hard cutting ...

  9. DETERMINATION OF LEAF AREA AND PLANT COVER BY USING DIGITAL IMAGE PROCESSING

    OpenAIRE

    LŐKE, ZS.; SOÓS, G.

    2002-01-01

    The development of different crop models, and crop simulation models in particular, pointed out the importance of quantifying the exact value of the leaf area. To measure the leaf size of plants of pinnatifid form, automatic, portable leaf area meters are necessary. In most places these instruments are not available to measure the assimilatory surface size of crops with special leaf shapes. Any cheap and effective method, that could replace the application of expensive portable area meters co...

  10. 75 FR 36347 - Determination of Pest-Free Areas in Mendoza Province, Argentina; Request for Comments

    Science.gov (United States)

    2010-06-25

    ... commodities that, based on the findings of a pest risk analysis, can be safely imported subject to one or more... Animal and Plant Health Inspection Service Determination of Pest-Free Areas in Mendoza Province... recognize additional areas as pest- free areas for Mediterranean fruit fly (Ceratitis capitata) in Argentina...

  11. 18 CFR 430.7 - Determination of protected areas and restriction on water use.

    Science.gov (United States)

    2010-04-01

    ... protected areas and restriction on water use. 430.7 Section 430.7 Conservation of Power and Water Resources... Determination of protected areas and restriction on water use. In consideration of the foregoing facts and for... a protected area within the meaning and for the purpose of Article 10 of the Delaware River Basin...

  12. 76 FR 51934 - Determination of Pest-Free Areas in Mendoza Province, Argentina; Request for Comments

    Science.gov (United States)

    2011-08-19

    ... acknowledged Argentina's history of successful Medfly control efforts, but stated that APHIS should not relax...] Determination of Pest-Free Areas in Mendoza Province, Argentina; Request for Comments AGENCY: Animal and Plant... received a request from the Government of Argentina to recognize additional areas as pest- free areas for...

  13. Study of measurement methods of ultrafine aerosols surface-area for characterizing occupational exposure

    International Nuclear Information System (INIS)

    Bau, S.

    2008-12-01

    This work aims at improving knowledge on ultrafine aerosols surface-area measurement. Indeed, the development of nano-technologies may lead to occupational exposure to airborne nano-structured particles, which involves a new prevention issue. There is currently no consensus concerning what parameter (mass, surface-area, number) should be measured. However, surface-area could be a relevant metric, since it leads to a satisfying correlation with biological effects when nano-structured particles are inhaled. Hence, an original theoretical work was performed to position the parameter of surface-area in relation to other aerosol characteristics. To investigate measurement techniques of nano-structured aerosols surface-area, the experimental facility CAIMAN (Characterization of Instruments for the Measurement of Aerosols of Nano-particles) was designed and built. Within CAIMAN, it is possible to produce nano-structured aerosols with varying and controlled properties (size, concentration, chemical nature, morphology, state-of-charge), stable and reproducible in time. The generated aerosols were used to experimentally characterize the response of the instruments in study (NSAM and AeroTrak 9000 TSI, LQ1-DC Matter Engineering). The response functions measured with monodisperse aerosols show a good agreement with the corresponding theoretical curves in a large size range, from 15 to 520 nm. Furthermore, hypotheses have been formulated to explain the reasonable biases observed when measuring poly-disperse aerosols. (author)

  14. Analysis of relationships between NDVI and land surface temperature in coastal area

    Science.gov (United States)

    Ning, Jicai; Gao, Zhiqiang; Chen, Maosi

    2017-09-01

    Using Landsat 5 Thematic Mapper and Landsat 8 Operational Land Imager and Thermal Infrared Sensor imagery of the Yellow River Delta, this study analyzed the relationships between NDVI and LST (land surface temperature). Six Landsat images comprising two time series were used to calculate the land surface temperature and correlated vegetation indices. The Yellow River Delta area has expanded substantially because of the deposited sediment carried from upstream reaches of the river. Between 1986 and 2015, approximately 35% of the land use area of the Yellow River Delta has been transformed into salterns and aquaculture ponds. Overall, land use conversion has occurred primarily from poorly utilized land into highly utilized land. To analyze the variation of land surface temperature, a mono-window algorithm was applied to retrieve the regional land surface temperature. The results showed bilinear correlation between land surface temperature and the vegetation indices (i.e., Normalized Difference Vegetation Index, Adjusted-Normalized Vegetation Index, Soil-Adjusted Vegetation Index, and Modified Soil-Adjusted Vegetation Index). Generally, values of the vegetation indices greater than the inflection point mean the land surface temperature and the vegetation indices are correlated negatively, and vice versa. Land surface temperature in coastal areas is affected considerably by local seawater temperature and weather conditions.

  15. Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada Appendix D - Corrective Action Investigation Report, Central Nevada Test Area, CAU 417

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Department of Energy, Nevada Operations office

    1999-04-02

    This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 417: Central Nevada Test Area Surface, Nevada, under the Federal Facility Agreement and Consent Order. Located in Hot Creek Valley in Nye County, Nevada, and consisting of three separate land withdrawal areas (UC-1, UC-3, and UC-4), CAU 417 is comprised of 34 corrective action sites (CASs) including 2 underground storage tanks, 5 septic systems, 8 shaker pad/cuttings disposal areas, 1 decontamination facility pit, 1 burn area, 1 scrap/trash dump, 1 outlier area, 8 housekeeping sites, and 16 mud pits. Four field events were conducted between September 1996 and June 1998 to complete a corrective action investigation indicating that the only contaminant of concern was total petroleum hydrocarbon (TPH) which was found in 18 of the CASs. A total of 1,028 samples were analyzed. During this investigation, a statistical approach was used to determine which depth intervals or layers inside individual mud pits and shaker pad areas were above the State action levels for the TPH. Other related field sampling activities (i.e., expedited site characterization methods, surface geophysical surveys, direct-push geophysical surveys, direct-push soil sampling, and rotosonic drilling located septic leachfields) were conducted in this four-phase investigation; however, no further contaminants of concern (COCs) were identified. During and after the investigation activities, several of the sites which had surface debris but no COCs were cleaned up as housekeeping sites, two septic tanks were closed in place, and two underground storage tanks were removed. The focus of this CADD was to identify CAAs which would promote the prevention or mitigation of human exposure to surface and subsurface soils with contaminant

  16. Relationship among land surface temperature and LUCC, NDVI in typical karst area.

    Science.gov (United States)

    Deng, Yuanhong; Wang, Shijie; Bai, Xiaoyong; Tian, Yichao; Wu, Luhua; Xiao, Jianyong; Chen, Fei; Qian, Qinghuan

    2018-01-12

    Land surface temperature (LST) can reflect the land surface water-heat exchange process comprehensively, which is considerably significant to the study of environmental change. However, research about LST in karst mountain areas with complex topography is scarce. Therefore, we retrieved the LST in a karst mountain area from Landsat 8 data and explored its relationships with LUCC and NDVI. The results showed that LST of the study area was noticeably affected by altitude and underlying surface type. In summer, abnormal high-temperature zones were observed in the study area, perhaps due to karst rocky desertification. LSTs among different land use types significantly differed with the highest in construction land and the lowest in woodland. The spatial distributions of NDVI and LST exhibited opposite patterns. Under the spatial combination of different land use types, the LST-NDVI feature space showed an obtuse-angled triangle shape and showed a negative linear correlation after removing water body data. In summary, the LST can be retrieved well by the atmospheric correction model from Landsat 8 data. Moreover, the LST of the karst mountain area is controlled by altitude, underlying surface type and aspect. This study provides a reference for land use planning, ecological environment restoration in karst areas.

  17. Surface Area of Patellar Facets: Inferential Statistics in the Iraqi Population

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Imam

    2017-01-01

    Full Text Available Background. The patella is the largest sesamoid bone in the body; its three-dimensional complexity necessitates biomechanical perfection. Numerous pathologies occur at the patellofemoral unit which may end in degenerative changes. This study aims to test the presence of statistical correlation between the surface areas of patellar facets and other patellar morphometric parameters. Materials and Methods. Forty dry human patellae were studied. The morphometry of each patella was measured using a digital Vernier Caliper, electronic balance, and image analyses software known as ImageJ. The patellar facetal surface area was correlated with patellar weight, height, width, and thickness. Results. Inferential statistics proved the existence of linear correlation of total facetal surface area and patellar weight, height, width, and thickness. The correlation was strongest for surface area versus patellar weight. The lateral facetal area was found persistently larger than the medial facetal area, the p value was found to be <0.001 (one-tailed t-test for right patellae, and another significant p value of < 0.001 (one-tailed t-test was found for left patellae. Conclusion. These data are vital for the restoration of the normal biomechanics of the patellofemoral unit; these are to be consulted during knee surgeries and implant designs and can be of an indispensable anthropometric, interethnic, and biometric value.

  18. Topography measurements for determining the decay factors in surface replication

    International Nuclear Information System (INIS)

    Song, J; Zheng, A; Vorburger, T V; Rubert, P

    2008-01-01

    The electro-forming technique is used at National Institute of Standards and Technology (NIST) for the production of standard reference material (SRM) 2461 standard casings to support nationwide ballistics measurement traceability and measurement quality control in the US. In order to ensure that the SRM casings are produced with virtually the same surface topography, it is necessary to test the decay factors of the replication process. Twenty-six replica casings are replicated from the same master casing for the decay factor tests. The NIST topography measurement system is used for measurements and correlations of surface topography. The topography decays are quantified by the cross-correlation function maximum CCF max . Based on the test, it is expected that 256 SRM casings can be replicated from the same master with CCF max values higher than 95%

  19. Surface Free Energy Determination of APEX Photosensitive Glass

    Directory of Open Access Journals (Sweden)

    William R. Gaillard

    2016-02-01

    Full Text Available Surface free energy (SFE plays an important role in microfluidic device operation. Photosensitive glasses such as APEX offer numerous advantages over traditional glasses for microfluidics, yet the SFE for APEX has not been previously reported. We calculate SFE with the Owens/Wendt geometric method by using contact angles measured with the Sessile drop technique. While the total SFE for APEX is found to be similar to traditional microstructurable glasses, the polar component is lower, which is likely attributable to composition. The SFE was modified at each stage of device fabrication, but the SFE of the stock and fully processed glass was found to be approximately the same at a value of 51 mJ·m−2. APEX exhibited inconsistent wetting behavior attributable to an inhomogeneous surface chemical composition. Means to produce more consistent wetting of photosensitive glass for microfluidic applications are discussed.

  20. Electronegativity determination of individual surface atoms by atomic force microscopy

    Czech Academy of Sciences Publication Activity Database

    Onoda, J.; Ondráček, Martin; Jelínek, Pavel; Sugimoto, Y.

    2017-01-01

    Roč. 8, Apr (2017), 1-6, č. článku 15155. ISSN 2041-1723 R&D Projects: GA ČR(CZ) GC14-16963J Institutional support: RVO:68378271 Keywords : AFM * DFT * electronegativity * surface science Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 12.124, year: 2016

  1. Surface-based determination of the pelvic coordinate system

    Science.gov (United States)

    Fieten, Lorenz; Eschweiler, Jörg; Heger, Stefan; Kabir, Koroush; Gravius, Sascha; de la Fuente, Matías; Radermacher, Klaus

    2009-02-01

    In total hip replacement (THR) one technical factor influencing the risk of dislocation is cup orientation. Computer-assisted surgery systems allow for cup navigation in anatomy-based reference frames. The pelvic coordinate system most used for cup navigation in THR is based on the mid-sagittal plane (MSP) and the anterior pelvic plane (APP). From a geometrical point of view, the MSP can be considered as a mirror plane, whereas the APP can be considered as a tangent plane comprising the anterior superior iliac spines (ASIS) and the pubic tubercles. In most systems relying on the pelvic coordinate system, the most anterior points of the ASIS and the pubic tubercles are selected manually. As manual selection of landmark points is a tedious, time-consuming and error-prone task, a surface-based approach for combined MSP and APP computation is presented in this paper: Homologous points defining the MSP and the landmark points defining the APP are selected automatically from surface patches. It is investigated how MSP computation can benefit from APP computation and vice versa, and clinical perspectives of combined MSP and APP computation are discussed. Experimental results on computed tomography data show that the surface-based approach can improve accuracy.

  2. Surface geoeletric sounding for the determination of aquifer ...

    African Journals Online (AJOL)

    ... which is probably clayey in profile 1. The third layer is a clayey sandy zone with low resistivity values. This is further underlain by a fourth layer whose resistivity range from 122-301 ohm-m. This layer is ascribed to be a sandy layer. This layer is identified as the aquifer of interest in the area. Nigerian Journal of Physics Vol.

  3. Geohydrology and susceptibility of major aquifers to surface contamination in Alabama; area 11

    Science.gov (United States)

    Castleberry, R.D.; Moreland, R.S.; Scott, J.C.

    1989-01-01

    This report delineates and describes the geohydrology and susceptibility of major aquifers to contamination in Butler, Conecuh, Covington, Crenshaw, Escambia, and Monroe Counties, Alabama. The major aquifers are the Pliocene-Miocene, Upper Floridan, Lisbon, Nanafalia-Clayton, and Providence-Ripley. The largest pumping centers in the area are Andalusia and Monroeville, where groundwater use is about 5 and 4 million gal/day, respectively. Estimated maximum withdrawal in 1987 for all uses in the area was about 44 million gal/day. Depressions have developed in the potentiometric surfaces of the Lisbon aquifer near Andalusia and Opp, the Nanafalia-Clayton aquifer near Luverne, Andalusia, Beatrice, and Monroeville, and the Providence-Ripley aquifer at Greenville. Significant declines in the potentiometric surfaces of the other major aquifers are not apparent. Recharge areas for all major aquifers are susceptible to contamination, but the probability of contamination of the Lisbon, Nanafalia-Clayton, and Providence-Ripley aquifers is low because the recharge areas are remote from areas of the withdrawal. The depressions in the recharge area for the Upper Floridan aquifer and the area where the Pliocene-Miocene aquifer is overlain by the gravelly sands of the Citronelle Formation are highly susceptible to contamination from the surface. (USGS)

  4. Microbiology of the surface water samples in the high background radiation areas of Ramsar, Iran

    International Nuclear Information System (INIS)

    Motamedifar, Mohammad; Zamani, Khosrow; Sedigh, Hadi; Mortazavi, Seyed Mohammad Javad; Taeb, Shahram; Haghani, M.; Mortazavi, Seyed Ali Reza; Soofi, Amir

    2014-01-01

    Residents of high background radiation areas of Ramsar have lived in these areas for many generations and received radiation doses much higher than the dose limit recommended by ICRP for radiation workers. The radioactivity of the high background radiation areas of Ramsar is reported to be due to 226 Ra and its decay products, which have been brought to the surface by the waters of hot springs. Over the past years the department has focused on different aspects of the health effects of the elevated levels of natural radiation in Ramsar. This study was aimed to perform a preliminary investigation on the bioeffects of exposure to elevated levels of natural radiation on the microbiology of surface water samples. Water samples were collected from surface water streams in Talesh Mahalleh district, Ramsar as well as a nearby area with normal levels of background radiation. Only two strains of bacteria, that is, Providencia stuartii and Shimwellia blattae, could be isolated from the water samples collected from high background radiation areas, while seven strains (Escherichia coli, Enterobacter asburiae, Klebsiella pneumoniae, Shigella dysenteriae, Buttiauxella agerstis, Tatumella punctuata and Raoultella ornithinolytica) were isolated from the water samples collected from normal background radiation areas. All the bacteria isolated from water samples of high and normal background radiation areas were sensitive to ultraviolet radiation, heat, betadine, alcohol, and deconex. Although other investigators have reported that bacteria isolated from hot springs show radioresistance, the results reported here do not reveal any adaptive response. (author)

  5. A Three-Dimensional Enormous Surface Area Aluminum Microneedle Array with Nanoporous Structure

    OpenAIRE

    Chen, Po Chun; Hsieh, Sheng Jen; Chen, Chien Chon; Zou, Jun

    2013-01-01

    We proposed fabricating an aluminum microneedle array with a nanochannel structure on the surface by combining micromachining, electrolyte polishing, and anodization methods. The microneedle array provides a three-dimensional (3D) structure that possesses several hundred times more surface area than a traditional nanochannel template. Therefore, the microneedle array can potentially be used in many technology applications. This 3D microneedle array device can not only be used for painless inj...

  6. Area-averaged surface fluxes and their time-space variability over the FIFE experimental domain

    Science.gov (United States)

    Smith, E. A.; Hsu, A. Y.; Crosson, W. L.; Field, R. T.; Fritschen, L. J.; Gurney, R. J.; Kanemasu, E. T.; Kustas, W. P.; Nie, D.; Shuttleworth, W. J.

    1992-01-01

    The underlying mean and variance properties of surface net radiation, sensible-latent heat fluxes and soil heat flux are studied over the densely instrumented grassland region encompassing FIFE. Flux variability is discussed together with the problem of scaling up to area-averaged fluxes. Results are compared and contrasted for cloudy and clear situations and examined for the influence of surface-induced biophysical controls (burn and grazing treatments) and topographic controls (aspect ratios and slope factors).

  7. DMSA scan nomograms for renal length and area: Related to patient age and to body weight, height or surface area

    International Nuclear Information System (INIS)

    Hassan, I.M.; Que, L.; Rutland, M.D.

    2002-01-01

    Aim: To create nomograms for renal size as measured from DMSA renal studies, and to test the nomograms for their ability to separate normal from abnormal kidneys. Method: Renal length was measured from posterior oblique views and renal area from posterior views. Results from 253 patients with bilateral normal kidneys were used to create nomograms for renal size relative to patient age, body height, weight or body surface area (BSA). The nomograms enclosed 95% of the normal kidneys, thus indicating the range for 95% confidence limits, and hence the specificity. Each nomogram was then tested against 46 hypertrophied kidneys and 46 damaged kidneys. Results: The results from nomograms of renal length and renal area, compared to age, body height, body weight and BSA are presented. For each nomogram, the range is presented as a fraction of the mean value, and the number of abnormal kidneys (hypertrophied or damaged) outside the normal range is presented as a percentage (indicating the sensitivity). Conclusion: Renal Area was no better than renal length for detecting abnormal kidneys. Patient age was the least useful method of normalisation. BSA normalisation produced the best results most frequently (narrower ranges and highest detection of abnormal kidneys)

  8. Heavy metal contamination in surface runoff sediments of the urban area of Vilnius, Lithuania

    Directory of Open Access Journals (Sweden)

    Gytautas Ignatavičius

    2017-02-01

    Full Text Available Surface runoff from urbanized territories carries a wide range of pollutants. Sediments in untreated runoff from direct discharge stormwater systems significantly contribute to urban waterway pollution. In this study, heavy metal (Pb, Zn, Cu, Cr, Ba, As and Fe contamination in surface runoff sediments of the urban area of the city of Vilnius was investigated. The surface runoff sediment samples were collected from seven dischargers with the highest volume rate of water flow and concentrations of suspended solids. The geospatial analysis of the distribution of heavy metals shows that there are several active pollution sources supplying the dischargers with contaminated sediments. Most of these areas are located in the central part of the city and in old town with intense traffic. Principal components analysis and t-test results clearly depicted the significantly different chemical compositions of winter and autumn surface sediment samples. The sampling approach and assessment of results provide a useful tool to examine the contamination that is generated in urban areas, distinguish pollution sources and give a better understanding of the importance of permeable surfaces and green areas.

  9. Relation between Mesophyll Surface Area, Photosynthetic Rate, and Illumination Level during Development for Leaves of Plectranthus parviflorus Henckel 1

    Science.gov (United States)

    Nobel, Park S.; Zaragoza, Lawrence J.; Smith, William K.

    1975-01-01

    The influence of illumination level during leaf development on the mesophyll cell surface area per unit leaf area (Ames/A), CO2 resistances, and the photosynthetic rate was determined for leaves of Plectranthus parviflorus Henckel. The relative importance of Ames/A versus CO2 resistances in accounting for observed changes in photosynthesis was quantitatively evaluated using equations based on analogies to electrical circuits. When the illumination during development was raised from 900 to 42,000 lux, the leaves more than tripled in thickness as the mesophyll cells increased in size and frequency, which caused Ames/A to go from 11 to 50. The net rate of photosynthesis at light saturation concomitantly increased 4-fold, reflecting a corresponding decrease in the total resistance for CO2 movement per unit leaf area. However, the CO2 resistance per unit area of mesophyll cells remained about 580 seconds per centimeter for leaves grown under 900 to 42,000 lux. Thus, for P. parviflorus, the increased photosynthetic rate for leaves developing under higher illuminations resulted from a higher Ames/A, not from changes in the CO2 resistances within individual mesophyll cells, expressed per unit area of cell surface. Results are discussed in terms of previously observed increases in thickness, internal leaf area, and photosynthetic rates for sun versus shade leaves on various plant species. PMID:16659211

  10. Dye-Sensitized Solar Cells Based on High Surface Area Nanocrystalline Zinc Oxide Spheres

    Directory of Open Access Journals (Sweden)

    Pavuluri Srinivasu

    2011-01-01

    Full Text Available High surface area nanocrystalline zinc oxide material is fabricated using mesoporous nanostructured carbon as a sacrificial template through combustion process. The resulting material is characterized by XRD, N2 adsorption, HR-SEM, and HR-TEM. The nitrogen adsorption measurement indicates that the materials possess BET specific surface area ca. 30 m2/g. Electron microscopy images prove that the zinc oxide spheres possess particle size in the range of 0.12 μm–0.17 μm. The nanocrystalline zinc oxide spheres show 1.0% of energy conversion efficiency for dye-sensitized solar cells.

  11. Volumes, Masses, and Surface Areas for Shippingport LWBR Spent Nuclear Fuel in a DOE SNF Canister

    International Nuclear Information System (INIS)

    J.W. Davis

    1999-01-01

    The purpose of this calculation is to estimate volumes, masses, and surface areas associated with (a) an empty Department of Energy (DOE) 18-inch diameter, 15-ft long spent nuclear fuel (SNF) canister, (b) an empty DOE 24-inch diameter, 15-ft long SNF canister, (c) Shippingport Light Water Breeder Reactor (LWBR) SNF, and (d) the internal basket structure for the 18-in. canister that has been designed specifically to accommodate Seed fuel from the Shippingport LWBR. Estimates of volumes, masses, and surface areas are needed as input to structural, thermal, geochemical, nuclear criticality, and radiation shielding calculations to ensure the viability of the proposed disposal configuration

  12. Pore Scale Heterogeneity in the Mineral Distribution, Surface Area and Adsorption in Porous Rocks

    Science.gov (United States)

    Lai, P. E. P.; Krevor, S. C.

    2014-12-01

    The impact of heterogeneity in chemical transport and reaction is not understood in continuum (Darcy/Fickian) models of reactive transport. This is manifested in well-known problems such as scale dependent dispersion and discrepancies in reaction rate observations made at laboratory and field scales [1]. Additionally, this is a source of uncertainty for carbon dioxide injection, which produces a reactive fluid-rock system particularly in carbonate rock reservoirs. A potential cause is the inability of the continuum approach to incorporate the impact of heterogeneity in pore-scale reaction rates. This results in part from pore-scale heterogeneities in surface area of reactive minerals [2, 3]. We use x-ray micro tomography to describe the non-normal 3-dimensional distribution of reactive surface area within a porous medium according to distinct mineral groups. Using in-house image processing techniques, thin sections, nitrogen BET surface area, backscattered electron imaging and energy dispersive spectroscopy, we compare the surface area of each mineral phase to those obtained from x-ray CT imagery. In all samples, there is little correlation between the reactive surface area fraction and the volumetric fraction of a mineral in a bulk rock. Berea sandstone was far less heterogeneous and has a characteristic pore size at which a surface area distribution may be used to quantify heterogeneity. In carbonates, heterogeneity is more complex and surface area must be characterized at multiple length scales for an accurate description of reactive transport. We combine the mineral specific surface area characterisation to dynamic tomography, imaging the flow of water and solutes, to observe flow dependent and mineral specific adsorption. The observations may contribute to the incorporation of experimentally based statistical descriptions of pore scale heterogeneity in reactive transport into upscaled models, moving it closer to predictive capabilities for field scale

  13. A process to enhance the specific surface area and capacitance of hydrothermally reduced graphene oxide

    KAUST Repository

    Alazmi, Amira

    2016-08-26

    The impact of post-synthesis processing in reduced graphene oxide materials for supercapacitor electrodes has been analyzed. A comparative study of vacuum, freeze and critical point drying was carried out for hydrothermally reduced graphene oxide demonstrating that the optimization of the specific surface area and preservation of the porous network are critical to maximize its supercapacitance performance. As described below, using a supercritical fluid as the drying medium, unprecedented values of the specific surface area (364 m2 g−1) and supercapacitance (441 F g−1) for this class of materials have been achieved.

  14. N2-specific surface area of ZrO2-montmorillonite MK-10 synthesis

    International Nuclear Information System (INIS)

    Muzakky; Imam Proyogo

    2016-01-01

    A measurements of N 2 -specific surface area of ZrO 2 -montmorillonite MK-10 synthesis have been done. The purpose of this study is to observed the effect of calcination on the a specific surface area (SSA N2 -BET) of ZrO 2 -montmorillonite MK-10 synthesis. Calcination were carried out at a 200°C; 400°C and 700°C. While the observations were made with surface area analyzer (SAA) and transmission electron microscopy (TEM). The measurement results obtained that SSA N2 -BET ZrO 2 -MK-10 obtained at 214 m 2 g -1 for before calcination and 195 m 2 g -1 after calcination at 400°C. The effected of calcination temperature will cause more towards of multilayer system surface, but the distribution of pore volume becomes smaller. Result of visualization of ZrO 2 -MK-10 surface that by means of TEM showed before calcination are more transparent and has a pore more. While calcination at 400°C has a darker impression and became multilayer and have a larger volume. Synthesized of ZrO 2 -MK 10 that using the ethylene glycol precursor have SSA N2 -BET higher than using glycerol is 195.33 m 2 g -1 and more memorable surface of a solid compact and orderly. (author)

  15. Observation of contact area of bubbles with heating surface in pool boiling of water under microgravity

    International Nuclear Information System (INIS)

    Suzuki, K.; Kawamura, H.; Suzuki, M.; Takahashi, S.; Abe, Y.

    2003-01-01

    Burnout heat flux was measured in subcooled pool boiling of water under attached boiling bubbles on heating surface with bubble holding plate in ground experiment. A thin stainless flat plate was employed for heating surface. The experimental setup and the heating procedures were same as used in reduced gravity experiment performed by a parabolic flight of jet aircraft. Same burnout heat flux as in the reduced gravity was obtained by adjusting the clearance between the bubble holder and the heating surface. They were 100 ∝ 400 percent higher than the widely accepted existing theories. As extending heating time longer than the reduced gravity duration until burnout occurred, burnout heat flux decreased gradually and became a constant value calculated from the existing theories. In a result of observing contact area of boiling bubbles with transparent heating surface, the contact area was smaller in quick heating time than that in long time heating at same heat flux. The experimental results suggest in microgravity that liquid layer is remained between rapidly expanded bubbles and heating surface. In microgravity experiment by a drop shaft facility, contact area of bubbles with heating surface increased considerably at starting of microgravity. (orig.)

  16. City landscape changes effects on land surface temperature in Bucharest metropolitan area

    Science.gov (United States)

    Savastru, Dan M.; Zoran, Maria A.; Savastru, Roxana S.; Dida, Adrian I.

    2017-10-01

    This study investigated the influences of city land cover changes and extreme climate events on land surface temperature in relationship with several biophysical variables in Bucharest metropolitan area of Romania through satellite and in-situ monitoring data. Remote sensing data from IKONOS, Landsat TM/ETM+ and time series MODIS Terra/Aqua and NOAA AVHRR sensors have been used to assess urban land cover- temperature interactions over 2000 - 2016 period. Time series Thermal InfraRed (TIR) satellite remote sensing data in synergy with meteorological data (air temperatureAT, precipitations, wind, solar radiation, etc.) were applied mainly for analyzing land surface temperature (LST) pattern and its relationship with surface landscape characteristics, assessing urban heat island (UHI), and relating urban land cover temperatures (LST). The land surface temperature, a key parameter for urban thermal characteristics analysis, was also analyzed in relation with the Normalized Difference Vegetation Index (NDVI) at city level. Results show that in the metropolitan area ratio of impervious surface in Bucharest increased significantly during investigated period, the intensity of urban heat island and heat wave events being most significant. The correlation analyses revealed that, at the pixel-scale, LST and AT possessed a strong positive correlation with percent impervious surfaces and negative correlation with vegetation abundances at metropolitan scale respectively. The NDVI was significantly correlated with precipitation. The spatial average air temperatures in urban test areas rise with the expansion of the urban size.

  17. Description of surface systems. Preliminary site description Simpevarp sub area - Version 1.2

    International Nuclear Information System (INIS)

    Lindborg, Tobias

    2005-03-01

    Swedish Nuclear Fuel and Waste Management Co is currently conducting site characterisation in the Simpevarp area. The area is divided into two subareas, the Simpevarp and the Laxemar subarea. The two subareas are surrounded by a common regional model area, the Simpevarp area. This report describes both the regional area and the subareas. This report is an interim version (model version 1.2) of the description of the surface systems at the Simpevarp area, and should be seen as a background report to the site description of the Simpevarp area, version 1.2, SKB-R--05-08. The basis for this description is quality-assured field data available in the SKB SICADA and GIS databases, together with generic data from the literature. The Surface system, here defined as everything above the bedrock, comprises a number of separate disciplines (e.g. hydrology, geology, topography, oceanography and ecology). Each discipline has developed descriptions and models for a number of properties that together represent the site description. The current methodology for developing the surface system description and the integration to ecosystem models is documented in a methodology strategy report SKB-R--03-06. The procedures and guidelines given in that report were followed in this report. Compared with version 1.1 of the surface system description SKB-R--04-25, this report presents considerable additional features, especially in the ecosystem description (Chapter 4) and in the description of the surface hydrology (Section 3.4). A first attempt has also been made to connect the flow of matter (carbon) between the different ecosystems into an overall ecosystem model at a landscape level. A summarised version of this report is also presented in SKB-R--05-08 together with geological-, hydrogeological-, transport properties-, thermal properties-, rock mechanics- and hydrogeochemical descriptions

  18. Description of surface systems. Preliminary site description Simpevarp sub area - Version 1.2

    Energy Technology Data Exchange (ETDEWEB)

    Lindborg, Tobias (ed.)

    2005-03-01

    Swedish Nuclear Fuel and Waste Management Co is currently conducting site characterisation in the Simpevarp area. The area is divided into two subareas, the Simpevarp and the Laxemar subarea. The two subareas are surrounded by a common regional model area, the Simpevarp area. This report describes both the regional area and the subareas. This report is an interim version (model version 1.2) of the description of the surface systems at the Simpevarp area, and should be seen as a background report to the site description of the Simpevarp area, version 1.2, SKB-R--05-08. The basis for this description is quality-assured field data available in the SKB SICADA and GIS databases, together with generic data from the literature. The Surface system, here defined as everything above the bedrock, comprises a number of separate disciplines (e.g. hydrology, geology, topography, oceanography and ecology). Each discipline has developed descriptions and models for a number of properties that together represent the site description. The current methodology for developing the surface system description and the integration to ecosystem models is documented in a methodology strategy report SKB-R--03-06. The procedures and guidelines given in that report were followed in this report. Compared with version 1.1 of the surface system description SKB-R--04-25, this report presents considerable additional features, especially in the ecosystem description (Chapter 4) and in the description of the surface hydrology (Section 3.4). A first attempt has also been made to connect the flow of matter (carbon) between the different ecosystems into an overall ecosystem model at a landscape level. A summarised version of this report is also presented in SKB-R--05-08 together with geological-, hydrogeological-, transport properties-, thermal properties-, rock mechanics- and hydrogeochemical descriptions.

  19. Area Factor Determinations for an Industrial Worker Exposed to a Concrete Slab End-State

    International Nuclear Information System (INIS)

    Jannik, G. Timothy; Lee, Patricia L.; Farfan, Eduardo B.; Roach, Jesse L.

    2008-01-01

    The U.S. Department of Energy's (DOE) Savannah River Site (SRS) is decommissioning many of its excess facilities through removal of the facility structures leaving only the concrete-slab foundations in place. Site-specific, risk-based derived concentration guideline levels (DCGLs) for radionuclides have been determined for a future industrial worker potentially exposed to residual contamination on these concrete slabs as described in Jannik. These risk-based DCGLs were estimated for an exposure area of 100 m 2 . During deactivation and decommissioning (D and D) operations at SRS, the need for area factors for larger and smaller contaminated areas arose. This paper compares the area factors determined for an industrial worker exposed to a concrete slab end-state for several radionuclides of concern at SRS with 1) the illustrative area factors provided in MARSSIM, 2) the area correction factors provided in the U.S. Environmental Protection Agency's (EPA) Soil Screening Guidance, and 3) the hot spot criterion for field application provided in the RESRAD User's Manual. The purpose of this site-specific assessment is to determine if any of the recommended area factors provided in the guidance documents could be utilized at SRS for field applications of the industrial worker DCGLs. Results show the area factors that were determined for an SRS industrial worker exposed to concrete slab end-states for the common radionuclides provided in the referenced guidance documents. In addition to the SRS site-specific area factors, the following area factors are provided for comparison: - Illustrative examples of outdoor area dose factors (MARSSIM); - Area correction factors as a function of source area (Soil Screening Guidance). Note: the area correction factors were inverted to correspond to a DCGL area factor. - Recommended area correction factors as a function of source area (Soil Screening Guidance); - Ranges for hot spot multiplication factors (RESRAD). As it can be seen

  20. Determination of near surface in-situ stresses

    International Nuclear Information System (INIS)

    Garritty, P.; Irvin, R.

    1983-06-01

    One of the major unknowns affecting aspects of underground construction and the geohydrology of rock masses is the magnitude and direction of the geostatic principal stresses in the earth's crust. This is particularly the case in near surface rocks where there are indications that high horizontal stresses may exist. The techniques, experiences and results of a preliminary rock stress measurement programme conducted at shallow depth in the Carnmenellis Granite, Cornwall, using C.S.I.R.O. triaxial hollow inclusion cells are described. (author)

  1. Temporal variations of surface water quality in urban, suburban and rural areas during rapid urbanization in Shanghai, China

    International Nuclear Information System (INIS)

    Wang Junying; Da Liangjun; Song Kun; Li Bailian

    2008-01-01

    As the economic and financial center of China, Shanghai has experienced an extensive urban expansion since the early 1980s, with an attendant cost in environmental degradation. We use an integrated pollution index to study the temporal variations of surface water quality in urban, suburban and rural areas between 1982 and 2005. Data on monitored cross-sections were collected from the Shanghai Environmental Monitoring Center. The results indicated that the spatial pattern of surface water quality was determined by the level of urbanization. Surface water qualities in urban and suburban areas were improved by strengthening the environmental policies and management, but were worsening in rural areas. The relationship between economic growth and surface water quality in Shanghai showed an inversed-U-shaped curve, which reflected a similar pattern in most developed countries. This research suggests that decision makers and city officials should be more aware of the recent pollution increases in Shanghai. - An integrated pollution index documents the deterioration of water quality in greater Shanghai, recently most serious in rural sections

  2. Evaporation and wetted area of single droplets on waxy and hairy leaf surfaces.

    Science.gov (United States)

    Zhu, H; Yu, Y; Ozkan, H E; Derksen, R C; Krause, C R

    2008-01-01

    Understanding the evaporation of pesticide droplets and wetting of Leaf surfaces can increase foliar application efficiency and reduce pesticide use. Evaporation time and wetted area of single pesticide droplets on hairy and waxy geranium leaf surfaces were measured under the controlled conditions for five droplet sizes and three relative humidities. The sprays used to form droplets included water, a nonionic colloidal polymer drift retardant, an alkyl polyoxyethylene surfactant, and an insecticide. Adding the surfactant into spray mixtures greatly increased droplet wetted area on the surfaces while droplet evaporation time was greatly reduced. Adding the drift retardant into spray mixture slightly increased the droplet evaporation time and the wetted area. Also, droplets had Longer evaporation times on waxy leaves than on hairy leaves for all droplet diameters and all relative humidity conditions. Increasing relative humidity could increase the droplet evaporation time greatly but did not change the the wetted area. The droplet evaporation time and wetted area increased exponentially as the droplet size increased. Therefore, droplet size, surface characteristics of the target, relative humidity, and chemical composition of the spray mixtures (water alone, pesticide, additives) should be included as important factors that affect the efficacy and efficiency of pesticide applications.

  3. Induction Thermography for Surface Crack Detection and Depth Determination

    Directory of Open Access Journals (Sweden)

    Beate Oswald-Tranta

    2018-02-01

    Full Text Available In the last few years, induction thermography has been established as a non-destructive testing method for localizing surface cracks in metals. The sample to be inspected is heated with a short induced electrical current pulse, and the infrared camera records—during and after the heating pulse—the temperature distribution at the surface. Transforming the temporal temperature development for each pixel to phase information makes not only highly reliable detection of the cracks possible but also allows an estimation of its depth. Finite element simulations were carried out to investigate how the phase contrast depends on parameters such as excitation frequency, pulse duration, material parameters, crack depth, and inclination angle of the crack. From these results, generalized functions for the dependency of the phase difference on all these parameters were derived. These functions can be used as an excellent guideline as to how measurement parameters should be optimized for a given material to be able to detect cracks and estimate their depth. Several experiments on different samples were also carried out, and the results compared with the simulations showed very good agreement.

  4. Surface radiological investigation of Trench 5 in Waste Area Grouping 7 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Goff, D.D.

    1991-08-01

    A surface radiological investigation of areas encompassing Trench 5 on the Oak Ridge Reservation (ORR) was conducted from May 1990 through November 1990. This survey was led by the author, assisted by various members of the Measurement Applications and Development (MAD) group of the Health and Safety Research Division (HASRD) of Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The purpose of the investigation was to determine the presence, nature, and extent of surface radiological contamination at Trench 5, the Homogeneous Reactor Experiment fuel wells, and surrounding areas. Based on the data obtained in the field, interim corrective measures were recommended to limit human exposure to radioactivity and to minimize insult to the environment. It should be stressed that this project was not intended to be a complete site characterization but rather to be a preliminary investigation into the potential contamination problem that might exist as a result of past operations at Trench 5

  5. Surface radiological investigation of Trench 5 in Waste Area Grouping 7 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Goff, D.D.

    1991-08-01

    A surface radiological investigation of areas encompassing Trench 5 on the Oak Ridge Reservation (ORR) was conducted from May 1990 through November 1990. This survey was led by the author, assisted by various members of the Measurement Applications and Development (MAD) group of the Health and Safety Research Division (HASRD) of Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The purpose of the investigation was to determine the presence, nature, and extent of surface radiological contamination at Trench 5, the Homogeneous Reactor Experiment fuel wells, and surrounding areas. Based on the data obtained in the field, interim corrective measures were recommended to limit human exposure to radioactivity and to minimize insult to the environment. It should be stressed that this project was not intended to be a complete site characterization but rather to be a preliminary investigation into the potential contamination problem that might exist as a result of past operations at Trench 5.

  6. Transparent self-cleaning lubricant-infused surfaces made with large-area breath figure patterns

    Science.gov (United States)

    Zhang, Pengfei; Chen, Huawei; Zhang, Liwen; Ran, Tong; Zhang, Deyuan

    2015-11-01

    Nepenthes pitcher inspired slippery lubricant-infused porous surfaces greatly impact the understanding of liquid-repellent surfaces construction and have attracted extensive attention in recent years due to their potential applications in self-cleaning, anti-fouling, anti-icing, etc. In this work, we have successfully fabricated transparent slippery lubricant-infused surfaces based on breath figure patterns (BFPs). Large-area BFPs with interconnected pores were initially formed on the glass substrate and then a suitable lubricant was added onto the surfaces. The interconnected pores in BFPs were able to hold the lubricant liquid in place and form a stable liquid/solid composite surface capable of repelling a variety of liquids. The liquid-repellent surfaces show extremely low critical sliding angles for various liquids, thus providing the surfaces with efficient self-cleaning property. It was also found that the liquid droplets' sliding behaviors on the surfaces were significantly influenced by the tilting angle of the substrate, liquid volume, liquid chemical properties, and pore sizes of the surfaces.

  7. Surface structure determinations of crystalline ionic thin films grown on transition metal single crystal surfaces by low energy electron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Joel Glenn [Univ. of California, Berkeley, CA (United States)

    2000-05-01

    The surface structures of NaCl(100), LiF(100) and alpha-MgCl2(0001) adsorbed on various metal single crystals have been determined by low energy electron diffraction (LEED). Thin films of these salts were grown on metal substrates by exposing the heated metal surface to a molecular flux of salt emitted from a Knudsen cell. This method of investigating thin films of insulators (ionic salts) on a conducting substrate (metal) circumvents surface charging problems that plagued bulk studies, thereby allowing the use of electron-based techniques to characterize the surface.

  8. Determination of karst collapse intensity indicator in area of nuclear power plant construction using incomplete data

    International Nuclear Information System (INIS)

    Sharapov, R

    2014-01-01

    The paper deals with the definition of karst collapse intensity. The technique for determining the intensity of karst formation and collapse on the basis of calculation and probabilistic method is given. Karst collapse formation is affected by a great variety of natural and anthropogenic factors. Each factor can vary quite widely. The paper describes a technique for determining karst collapse intensity from incomplete data. It uses karst processes monitoring data in the area and monitoring data of areas with similar values of the most significant factors leading to the karst collapses. The method used for determination of karst collapse intensity indicator in area of Nizhny Novgorod nuclear power plant construction

  9. Reliable nanomaterial classification of powders using the volume-specific surface area method

    Energy Technology Data Exchange (ETDEWEB)

    Wohlleben, Wendel, E-mail: wendel.wohlleben@basf.com [Department of Material Physics, BASF SE (Germany); Mielke, Johannes [BAM–Federal Institute for Materials Research and Testing (Germany); Bianchin, Alvise [MBN Nanomaterialia s.p.a (Italy); Ghanem, Antoine [R& I Centre Brussels, Solvay (Belgium); Freiberger, Harald [Department of Material Physics, BASF SE (Germany); Rauscher, Hubert [European Commission, Nanobiosciences Unit, Joint Research Centre (Italy); Gemeinert, Marion; Hodoroaba, Vasile-Dan, E-mail: dan.hodoroaba@bam.de [BAM–Federal Institute for Materials Research and Testing (Germany)

    2017-02-15

    The volume-specific surface area (VSSA) of a particulate material is one of two apparently very different metrics recommended by the European Commission for a definition of “nanomaterial” for regulatory purposes: specifically, the VSSA metric may classify nanomaterials and non-nanomaterials differently than the median size in number metrics, depending on the chemical composition, size, polydispersity, shape, porosity, and aggregation of the particles in the powder. Here we evaluate the extent of agreement between classification by electron microscopy (EM) and classification by VSSA on a large set of diverse particulate substances that represent all the anticipated challenges except mixtures of different substances. EM and VSSA are determined in multiple labs to assess also the level of reproducibility. Based on the results obtained on highly characterized benchmark materials from the NanoDefine EU FP7 project, we derive a tiered screening strategy for the purpose of implementing the definition of nanomaterials. We finally apply the screening strategy to further industrial materials, which were classified correctly and left only borderline cases for EM. On platelet-shaped nanomaterials, VSSA is essential to prevent false-negative classification by EM. On porous materials, approaches involving extended adsorption isotherms prevent false positive classification by VSSA. We find no false negatives by VSSA, neither in Tier 1 nor in Tier 2, despite real-world industrial polydispersity and diverse composition, shape, and coatings. The VSSA screening strategy is recommended for inclusion in a technical guidance for the implementation of the definition.

  10. Determination of surface parameters and fluxes for climate studies from space observation. Methods, results and problems

    Science.gov (United States)

    Becker, F.; Seguin, B.

    Climate being the result of many interconnected processes, it can hardly be understood without models which describe these various processes as quantitatively as possible and define the parameters which are relevant for climate studies. Among those, surface processes and therefore surface parameters are now recognized to be of great importance. Some examples are discussed in the first part, showing the great interest to measure the relevant parameters on a multi-year basis, over large areas with sufficiently dense array and on a stable basis, in order to monitor climate changes or to study the impact on climate of the modifications of some relevant parameters which are analysed. Since space observations from satellites fulfil these requirements, it is clear that they will become very soon a fundamental tool for climate studies. Unfortunately, as it is discussed in the second part, satellites do measure only spectral radiances at the top of the atmosphere and the determination of the relevant surface parameters (or fluxes) from these radiances still raises many problems which have to be solved, although many progresses have already been made. The aim of this paper is therefore to review and discuss these problems and the various ways they have been tackled until now. The first part is devoted to an overview of what needs to be measured and why, while the existing methods for determining the most important surface parameters from space observations are presented in the second part where a particular attention is given to the theoretical and experimental validations of these methods, their limits and the problems still to be solved.

  11. Surface area and the seabed area, volume, depth, slope, and topographic variation for the world's seas, oceans, and countries.

    Science.gov (United States)

    Costello, Mark John; Cheung, Alan; De Hauwere, Nathalie

    2010-12-01

    Depth and topography directly and indirectly influence most ocean environmental conditions, including light penetration and photosynthesis, sedimentation, current movements and stratification, and thus temperature and oxygen gradients. These parameters are thus likely to influence species distribution patterns and productivity in the oceans. They may be considered the foundation for any standardized classification of ocean ecosystems and important correlates of metrics of biodiversity (e.g., species richness and composition, fisheries). While statistics on ocean depth and topography are often quoted, how they were derived is rarely cited, and unless calculated using the same spatial resolution the resulting statistics will not be strictly comparable. We provide such statistics using the best available resolution (1-min) global bathymetry, and open source digital maps of the world's seas and oceans and countries' Exclusive Economic Zones, using a standardized methodology. We created a terrain map and calculated sea surface and seabed area, volume, and mean, standard deviation, maximum, and minimum, of both depth and slope. All the source data and our database are freely available online. We found that although the ocean is flat, and up to 71% of the area has a ocean volume exceeds 1.3 billion km(3) (or 1.3 sextillion liters), and sea surface and seabed areas over 354 million km(2). We propose the coefficient of variation of slope as an index of topographic heterogeneity. Future studies may improve on this database, for example by using a more detailed bathymetry, and in situ measured data. The database could be used to classify ocean features, such as abyssal plains, ridges, and slopes, and thus provide the basis for a standards based classification of ocean topography.

  12. Closure Report for Corrective Action Unit 300: Surface Release Areas Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Restoration

    2007-07-01

    Corrective Action Unit (CAU) 300 is located in Areas 23, 25, and 26 of the Nevada Test Site, which is located approximately 65 miles northwest of Las Vegas, Nevada. CAU 300 is listed in the Federal Facility Agreement and Consent Order of 1996 as Surface Release Areas and is comprised of the following seven Corrective Action Sites (CASs), which are associated with the identified Building (Bldg): {sm_bullet} CAS 23-21-03, Bldg 750 Surface Discharge {sm_bullet} CAS 23-25-02, Bldg 750 Outfall {sm_bullet} CAS 23-25-03, Bldg 751 Outfall {sm_bullet} CAS 25-60-01, Bldg 3113A Outfall {sm_bullet} CAS 25-60-02, Bldg 3901 Outfall {sm_bullet} CAS 25-62-01, Bldg 3124 Contaminated Soil {sm_bullet} CAS 26-60-01, Bldg 2105 Outfall and Decon Pad The Nevada Division of Environmental Protection (NDEP)-approved corrective action alternative for CASs 23-21-03, 23-25-02, and 23-25-03 is no further action. As a best management practice, approximately 48 feet of metal piping was removed from CAS 23-25-02 and disposed of as sanitary waste. The NDEP-approved corrective action alternative for CASs 25-60-01, 25-60-02, 25-62-01, and 26-60-01, is clean closure. Closure activities for these CASs included removing and disposing of soil impacted with total petroleum hydrocarbons-diesel range organics (TPH-DRO), polychlorinated biphenyls (PCBs), semivolatile organic compounds (SVOCs), and cesium (Cs)-137, concrete impacted with TPH-DRO, and associated piping impacted with TPH-DRO. CAU 300 was closed in accordance with the NDEP-approved CAU 300 Corrective Action Plan (CAP) (U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSA/NSO], 2006). The closure activities specified in the CAP were based on the recommendations presented in the CAU 300 Corrective Action Decision Document (NNSA/NSO, 2005). This Closure Report documents CAU 300 closure activities. During closure activities, approximately 40 cubic yards (yd3) of low-level waste consisting of TPH-DRO-, PCB

  13. Snow specific surface area simulation using the one-layer snow model in the Canadian LAnd Surface Scheme (CLASS

    Directory of Open Access Journals (Sweden)

    A. Roy

    2013-06-01

    Full Text Available Snow grain size is a key parameter for modeling microwave snow emission properties and the surface energy balance because of its influence on the snow albedo, thermal conductivity and diffusivity. A model of the specific surface area (SSA of snow was implemented in the one-layer snow model in the Canadian LAnd Surface Scheme (CLASS version 3.4. This offline multilayer model (CLASS-SSA simulates the decrease of SSA based on snow age, snow temperature and the temperature gradient under dry snow conditions, while it considers the liquid water content of the snowpack for wet snow metamorphism. We compare the model with ground-based measurements from several sites (alpine, arctic and subarctic with different types of snow. The model provides simulated SSA in good agreement with measurements with an overall point-to-point comparison RMSE of 8.0 m2 kg–1, and a root mean square error (RMSE of 5.1 m2 kg–1 for the snowpack average SSA. The model, however, is limited under wet conditions due to the single-layer nature of the CLASS model, leading to a single liquid water content value for the whole snowpack. The SSA simulations are of great interest for satellite passive microwave brightness temperature assimilations, snow mass balance retrievals and surface energy balance calculations with associated climate feedbacks.

  14. Are the surface areas of the gills and body involved with changing metabolic scaling with temperature?

    Science.gov (United States)

    Li, Ge; Lv, Xiao; Zhou, Jing; Shen, Cong; Xia, Danyang; Xie, Hang; Luo, Yiping

    2018-03-20

    The metabolic-level boundaries (MLB) hypothesis proposes that metabolic level mediates the relative influence of surface area (SA) vs volume related metabolic processes on the body-mass scaling of metabolic rate in organisms. The variation in the scaling of SA may affect how metabolic level affects the metabolic scaling exponent. This study aimed to determine the influence of increasing metabolic level at a higher temperature on the metabolic scaling exponent of the crucian carp and determine the link between metabolic scaling exponents and SA parameters of both gills and body. The SA of gills and body and the resting metabolic rate (RMR) of the crucian carp were assessed at 15 o C and 25 o C, and their mass scaling exponents were analyzed. The results showed a significantly higher RMR, with a lower scaling exponent, in the crucian carp at a higher temperature. The gills SA and the total SA of the fish (TSA) are reduced with the increasing temperature. The b RMR tends to be close to that of the TSA at a higher temperature. This suggests that temperature positively affects metabolic level but negatively affects the scaling exponent of RMR ( b RMR ). The findings support the MLB hypothesis. The lower scaling exponent at a higher temperature can be alternatively explained as that the higher viscosity of cold water impedes respiratory ventilation and oxygen uptake and reduces MR more in smaller individuals than in larger individuals at lower temperature, thus resulting in a negative association between temperature and b RMR . © 2018. Published by The Company of Biologists Ltd.

  15. Impact of microstructure evolution on the difference between geometric and reactive surface areas in natural chalk

    Science.gov (United States)

    Yang, Y.; Bruns, S.; Stipp, S. L. S.; Sørensen, H. O.

    2018-05-01

    The coupling between flow and mineral dissolution drives the evolution of many natural and engineered flow systems. Pore surface changes as microstructure evolves but this transient behaviour has traditionally been difficult to model. We combined a reactor network model with experimental, greyscale tomography data to establish the morphological grounds for differences among geometric, reactive and apparent surface areas in dissolving chalk. This approach allowed us to study the effects of initial geometry and macroscopic flow rate independently. The simulations showed that geometric surface, which represents a form of local transport heterogeneity, increases in an imposed flow field, even when the porous structure is chemically homogeneous. Hence, the fluid-reaction coupling leads to solid channelisation, which further results in fluid focusing and an increase in geometric surface area. Fluid focusing decreases the area of reactive surface and the residence time of reactant, both contribute to the over-normalisation of reaction rate. In addition, the growing and merging of microchannels, near the fluid entrance, contribute to the macroscopic, fast initial dissolution rate of rocks.

  16. Changes in thickness and surface area of the human cortex and their relationship with intelligence.

    Science.gov (United States)

    Schnack, Hugo G; van Haren, Neeltje E M; Brouwer, Rachel M; Evans, Alan; Durston, Sarah; Boomsma, Dorret I; Kahn, René S; Hulshoff Pol, Hilleke E

    2015-06-01

    Changes in cortical thickness over time have been related to intelligence, but whether changes in cortical surface area are related to general cognitive functioning is unknown. We therefore examined the relationship between intelligence quotient (IQ) and changes in cortical thickness and surface over time in 504 healthy subjects. At 10 years of age, more intelligent children have a slightly thinner cortex than children with a lower IQ. This relationship becomes more pronounced with increasing age: with higher IQ, a faster thinning of the cortex is found over time. In the more intelligent young adults, this relationship reverses so that by the age of 42 a thicker cortex is associated with higher intelligence. In contrast, cortical surface is larger in more intelligent children at the age of 10. The cortical surface is still expanding, reaching its maximum area during adolescence. With higher IQ, cortical expansion is completed at a younger age; and once completed, surface area decreases at a higher rate. These findings suggest that intelligence may be more related to the magnitude and timing of changes in brain structure during development than to brain structure per se, and that the cortex is never completed but shows continuing intelligence-dependent development. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Abacus for the determination of the groundwater evaporation in arid areas. Case of the region of Ouargla-Algeria

    Science.gov (United States)

    El Fergougui, Myriam Marie; Boutoutaou, Djamel

    2016-07-01

    One of the possible remedies to control the inputs of salts toward the surface would be by diminishing the groundwater; because areas set on values in arid zones of the region of Ouargla are based upon excessively mineralized groundwater whose level is near the ground surface (0 to 1.5 m). The improvement and stabilization of yields of any cultural practices in these areas can only take place if the salty groundwater is maintained (drained) to a depth of 1.6m. The results of work carried on the determination of the groundwater evaporation in Ouargla show that the evaporation essentially depends on: The climate that reigns above the ground of the groundwater situated on the band from 0 to 0.6 m. The climate and soil texture according the groundwater located in the layer from 0.6 to 1.6 m. The depth of the groundwater when this latter is located beyond 1.6 m.

  18. Quality of surface-water supplies in the Triangle area of North Carolina, water year 2008

    Science.gov (United States)

    Giorgino, M.J.; Rasmussen, R.B.; Pfeifle, C.A.

    2012-01-01

    Surface-water supplies are important sources of drinking water for residents in the Triangle area of North Carolina, which is located within the upper Cape Fear and Neuse River Basins. Since 1988, the U.S. Geological Survey and a consortium of governments have tracked water-quality conditions and trends in several of the area's water-supply lakes and streams. This report summarizes data collected through this cooperative effort, known as the Triangle Area Water Supply Monitoring Project, during October 2007 through September 2008. Major findings for this period include:

  19. Lp-dual affine surface area forms of Busemann–Petty type problems

    Indian Academy of Sciences (India)

    (Math. Sci.) Vol. 125, No. 1, February 2015, pp. 71–77. c Indian Academy of Sciences. Lp-dual affine surface area forms of Busemann–Petty type problems ..... problem in three dimensions,. Ann. Math. 140(2) (1994) 435–447. [4] Gardner R J, Geometric tomography, 2nd edn (2006) (Cambridge, UK: Cambridge Univ. Press).

  20. Specific surface area behavior of a dissolving population of particles. Augmenting Mercer Dissolution Theory

    International Nuclear Information System (INIS)

    Scripsick, R.C.; Rothenberg, S.J.

    1986-01-01

    Specific surface area (Sp) measurements were made on two uranium oxide aerosol materials before and after in vitro dissolution studies were performed on the materials. The results of these Sp measurements were evaluated relative to predictions made from extending Mercer dissolution theory to describe the Sp behavior of a dissolving population of particles

  1. Periodic Mesoporous Organosilica Nanocubes with Ultrahigh Surface Areas for Efficient CO2 Adsorption

    Science.gov (United States)

    Wei, Yong; Li, Xiaomin; Zhang, Renyuan; Liu, Yong; Wang, Wenxing; Ling, Yun; El-Toni, Ahmed Mohamed; Zhao, Dongyuan

    2016-02-01

    Ultrahigh surface area single-crystals of periodic mesoporous organosilica (PMOs) with uniform cubic or truncated-cubic morphology and organic/inorganic components homogeneously distributed over the whole frameworks have successfully been prepared by a sol-gel surfactant-templating method. By tuning the porous feature and polymerization degree, the surface areas of the obtained PMO nanocubes can reach as high as 2370 m2/g, which is the highest for silica-based mesoporous materials. The ultrahigh surface area of the obtained PMO single crystals is mainly resulted from abundant micropores in the mesoporous frameworks. Furthermore, the diameter of the nanocubes can also be well controlled from 150 to 600 nm. The materials show ultrahigh CO2 adsorption capacity (up to 1.42 mmol/g at 273 K) which is much higher than other porous silica materials and comparable to some carbonaceous materials. The adsorption of CO2 into the PMO nanocubes is mainly in physical interaction, therefore the adsorption-desorption process is highly reversible and the adsorption capacity is much dependent on the surface area of the materials. Moreover, the selectivity is also very high (~11 times to N2) towards CO2 adsorption.

  2. Area densitometry using rotating Scheimpflug photography for posterior capsule opacification and surface light scattering analyses.

    Science.gov (United States)

    Minami, Keiichiro; Honbo, Masato; Mori, Yosai; Kataoka, Yasushi; Miyata, Kazunori

    2015-11-01

    To compare area densitometry analysis using rotating Scheimpflug photography in quantifications of posterior capsule opacification (PCO) and surface light scattering with previous anterior-segment analyzer measurement. Miyata Eye Hospital, Miyazaki, Japan. Prospective observational case series. Scheimpflug images of eyes with foldable intraocular lenses (IOLs) were obtained using rotating and fixed Scheimpflug photography. Area densitometry on the posterior and anterior surfaces was conducted for PCO and surface light scattering analyses, respectively, with an identical area size. Correlation between two measurements was analyzed using linear regression. The study included 105 eyes of 74 patients who received IOLs 1 to 18 years (mean, 4.9 ± 4.5 years) postoperatively. In the PCO analysis on the posterior IOL surface, there was a significant correlation between the two measurements (P photography exhibited saturation due to intensive scatterings. Area densitometry combined with a rotating Scheimpflug photography was exchangeable to previously established densitometry measurement, and allowed successive evaluation in longer-term observations. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  3. Characterization of pigment-leached antifouling coatings using BET surface area measurements and mercury porosimetry

    DEFF Research Database (Denmark)

    Kiil, Søren; Dam-Johansen, Kim

    2007-01-01

    In this work BET surface area measurements and mercury porosimetry are used to characterize leached layers formed when seawater-soluble pigments (Cu2O and ZnO) dissolve during accelerated leaching of simple antifouling coatings. Measurements on single-pigment coatings show that an increasing...

  4. Surface area of lactose and lactose granulates on consolidation and compaction

    NARCIS (Netherlands)

    Riepma, Klaas Alouis

    1993-01-01

    This dissertation discusses the effect of short time storage at different conditions on the strength and the specific BET surface area of lactose tablets. In addition, some aspects are studied of the consolidation and compaction properties of crystalline lactose fractions in heterogeneous systems.

  5. Dose banding as an alternative to body surface area-based dosing of chemotherapeutic agents

    NARCIS (Netherlands)

    E. Chatelut (Etienne); M.L. White-Koning (M.); A.H.J. Mathijssen (Ron); F. Puisset (F.); S.D. Baker (Sharyn); A. Sparreboom (Alex)

    2012-01-01

    textabstractBackground: Dose banding is a recently suggested dosing method that uses predefined ranges (bands) of body surface area (BSA) to calculate each patients dose by using a single BSA-value per band. Thus, drugs with sufficient long-term stability can be prepared in advance. The main

  6. High surface area carbon for bifunctional air electrodes applied in zinc-air batteries

    Energy Technology Data Exchange (ETDEWEB)

    Arai, H. [on leave from NTT Laboratories (Japan); Mueller, S.; Haas, O. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Bifunctional air electrodes with high surface area carbon substrates showed low reduction overpotential, thus are promising for enhancing the energy efficiency and power capability of zinc-air batteries. The improved performance is attributed to lower overpotential due to diffusion of the reaction intermediate, namely the peroxide ion. (author) 1 fig., 2 refs.

  7. A method for increasing the surface area of perovskite-type oxides

    Indian Academy of Sciences (India)

    combustion of methane at different temperatures (450–600oC) has been thoroughly investigated. The hydrothermal treatments result in the activation of the perovskite oxides by increasing their surface area very markedly. Keywords. ABO3-type perovskite oxides; LaCoO3; LaMnO3; hydrothermal treatment; catalytic ...

  8. Should blood flow during cardiopulmonary bypass be individualized more than to body surface area?

    DEFF Research Database (Denmark)

    Thomassen, Sisse Anette; Larsson, A; Andreasen, Jan Jesper

    Blood flow during cardiopulmonary bypass (CPB) is calculated on body surface area (BSA). Increasing comorbidity, age and weight of today's cardiac patients question this calculation as it may not reflect individual metabolic requirement. The hypothesis was that a measured cardiac index (CI) prior...... not improve cerebral and systemic oxygenation compared to a blood flow based on BSA....

  9. Mapping surface flow in low gradient areas with thermal remote sensing

    DEFF Research Database (Denmark)

    Prinds, Christian; Petersen, Rasmus Jes; Greve, Mogens Humlekrog

    Thermal infrared (TIR) imagery has long been used for mapping groundwater-surface water interactions and mainly for locating areas of groundwater seepage in lakes and shorelines (Rundquist et al. 1985, Banks et al. 1996). In this study, we used the method for locating discharge from tile drains...

  10. A method for increasing the surface area of perovskite-type oxides

    Indian Academy of Sciences (India)

    700oC (v), 800oC ( ) and without water treatment (U). The increase in the surface area of the perovskite-type oxides and the observed decrease in the crystal size by the steam treatment at 350–800oC are expected because of the recrystallization during the high temperature hydrothermal treatment depending upon the.

  11. Amylolytic hydrolysis of native starch granules affected by granule surface area.

    Science.gov (United States)

    Kim, J C; Kong, B W; Kim, M J; Lee, S H

    2008-11-01

    Initial stage of hydrolysis of native starch granules with various amylolytic enzymes, alpha-amylase from Bacillus subtilis, glucoamylase I (GA-I) and II (GA-II) from Aspergillus niger, and beta-amylase from sweet potato showed that the reaction was apparently affected by a specific surface area of the starch granules. The ratios of the reciprocal of initial velocity of each amylolytic hydrolysis for native potato and maize starch to that for rice with the amylolytic enzymes were nearly equivalent to the ratio of surface area per mass of the 2 starch granules to that of rice, that is, 6.94 and 2.25, respectively. Thus, the reciprocal of initial velocity of each enzymatic hydrolysis as expressed in a Lineweaver-Burk plot was a linear function of the reciprocal of surface area for each starch granule. As a result, it is concluded that amylolytic hydrolysis of native starch granules is governed by the specific surface area, not by the mass concentration, of each granule.

  12. Preparation of MgO Catalytic Support in Shaped Mesoporous High Surface Area Form

    Czech Academy of Sciences Publication Activity Database

    Gulková, Daniela; Šolcová, Olga; Zdražil, Miroslav

    2004-01-01

    Roč. 76, 1-3 (2004), s. 137-149 ISSN 1387-1811 R&D Projects: GA AV ČR IAA4072306 Institutional research plan: CEZ:AV0Z4072921 Keywords : MgO support * sigh Surface area * texture Subject RIV: CC - Organic Chemistry Impact factor: 2.093, year: 2004

  13. Thermal stability of porous sol-gel phosphosilicates and their surface area stabilisation by lanthanum addition

    NARCIS (Netherlands)

    Falco, Lorena; De Mendonca, Mariana Van Den Tempel; Mercadal, Juan J.; Zarubina, Valeriya; Melián-Cabrera, Ignacio

    2016-01-01

    The thermal stability of porous sol-gel phosphosilicates was studied by comparing the textural features upon calcination between 400 and 550 °C. A significant loss of surface area and pore volume were observed; the first is due to thermal coarsening of the nanoparticles, and the pore volume

  14. Allometric relationships for surface area and dry mass of young Norway spruce aboveground organs

    Czech Academy of Sciences Publication Activity Database

    Pokorný, Radek; Tomášková, Ivana

    53 2007, č. 12 (2007), s. 548-554 ISSN 1212-4834 R&D Projects: GA MŽP(CZ) SP/2D1/93/07 Institutional research plan: CEZ:AV0Z60870520 Keywords : allometry * biomass, * Picea abies * sapwood * surface area Subject RIV: GK - Forestry

  15. Estimating the surface area of non-convex particles from central planar sections

    DEFF Research Database (Denmark)

    Thórisdóttir, Ólöf; H.Rafati, Ali; Kiderlen, Markus

    . The Morse type estimator is well suited for computer assisted confocal microscopy and we demonstrate its practicability in a biological application: the surface area estimation of the nuclei of giant-cell glioblastoma from microscopy images. We also present an interactive software that allows the user...

  16. Flow analysis of water-powder mixtures: Application to specific surface area and shape factor

    NARCIS (Netherlands)

    Hunger, Martin; Brouwers, Jos

    2009-01-01

    This paper addresses the characterization of powder materials with respect to their application in concrete. Given that powders provide by far highest percentage of specific surface area in a concrete mix, their packing behavior and water demand is of vital interest for the design of concrete. They

  17. Turbostratic boron nitride coated on high-surface area metal oxide templates

    DEFF Research Database (Denmark)

    Klitgaard, Søren Kegnæs; Egeblad, Kresten; Brorson, M.

    2007-01-01

    Boron nitride coatings on high-surface area MgAl2O4 and Al2O3 have been synthesized and characterized by transmission electron microscopy and by X-ray powder diffraction. The metal oxide templates were coated with boron nitride using a simple nitridation in a flow of ammonia starting from ammonium...

  18. Condensation-Enhanced Self-Assembly as a Route to High Surface Area alpha-Aluminas

    NARCIS (Netherlands)

    Perez, Lidia Lopez; Zarubina, Valeriya; Heeres, Hero Jan; Melian-Cabrera, Ignacio

    2013-01-01

    High surface area nanosized alpha-alumina has been obtained by thermally treating a sol-gel-derived mesophase at 1200 degrees C; the mesophase was synthesized by a sol-gel route involving evaporation induced self-assembly (EISA) of a hydrolyzed gel from Al-tri-sec-butoxide in s-BuOH in the presence

  19. Uncovering surface area and micropores in almond shell biochars by rainwater wash

    Science.gov (United States)

    Biochars have been considered for adsorption of contaminants in soil and water, as well as conditioning and improving soil quality. One important property of the biochar is surface area in the pores of the biochar. Biochars were created from almond shells from two almond varieties with different ash...

  20. Surface water and groundwater interaction in selected areas of Indus basin

    International Nuclear Information System (INIS)

    Akram, W.; Ahmad, M.; Tariq, J.A.; Latif, Z.; Malik, M.R.

    2011-08-01

    Isotope hydrological investigations were carried out in Marala-Khanki Area of Punjab for elucidating various aspects of surface water and groundwater interaction. Groundwater samples were collected on seasonal basis (low and high river discharge periods) while surface water (Chenab River) samples were collected more frequently (weekly or monthly basis). Isotopic data suggested that there is no significant contribution of surface water to groundwater recharge in Marala-Khanki Area and rain is the prevailing source of groundwater recharge. The data further revealed that isotopic values of Tarbala lake are higher than those of main lake. Indus river meaning that there is significant contribution of base flow in this pocket. Isotopic data of Indus river showed an increase at Tunsa as compared to Chashma in flow period indicating the high contribution of base flow at this point in time. Stable isotopes were successfully used to quantify the base flow contribution. (author)

  1. A Three-Dimensional Enormous Surface Area Aluminum Microneedle Array with Nanoporous Structure

    Directory of Open Access Journals (Sweden)

    Po Chun Chen

    2013-01-01

    Full Text Available We proposed fabricating an aluminum microneedle array with a nanochannel structure on the surface by combining micromachining, electrolyte polishing, and anodization methods. The microneedle array provides a three-dimensional (3D structure that possesses several hundred times more surface area than a traditional nanochannel template. Therefore, the microneedle array can potentially be used in many technology applications. This 3D microneedle array device can not only be used for painless injection or extraction, but also for storage, highly sensitive detection, drug delivery, and microelectrodes. From the calculation we made, the microneedle array not only increases surface area, but also enlarges the capacity of the device. Therefore, the microneedle array can further be used on many detecting, storing, or drug delivering applications.

  2. A Three-Dimensional Enormous Surface Area Aluminum Microneedle Array with Nanoporous Structure

    International Nuclear Information System (INIS)

    Chen, P.Ch.; Zou, J.; Hsieh, Sh.J.; Chen, Ch.Ch.

    2013-01-01

    We proposed fabricating an aluminum micro needle array with a nano channel structure on the surface by combining micromachining, electrolyte polishing, and anodization methods. The micro needle array provides a three-dimensional (3D) structure that possesses several hundred times more surface area than a traditional nano channel template. Therefore, the micro needle array can potentially be used in many technology applications. This 3D micro needle array device can not only be used for painless injection or extraction, but also for storage, highly sensitive detection, drug delivery, and microelectrodes. From the calculation we made, the micro needle array not only increases surface area, but also enlarges the capacity of the device. Therefore, the micro needle array can further be used on many detecting, storing, or drug delivering applications.

  3. Seeded on-surface supramolecular growth for large area conductive donor-acceptor assembly.

    Science.gov (United States)

    Goudappagouda; Chithiravel, Sundaresan; Krishnamoorthy, Kothandam; Gosavi, Suresh W; Babu, Sukumaran Santhosh

    2015-07-04

    Charge transport features of organic semiconductor assemblies are of paramount importance. However, large-area extended supramolecular structures of donor-acceptor combinations with controlled self-assembly pathways are hardly accessible. In this context, as a representative example, seeded on-surface supramolecular growth of tetrathiafulvalene and tetracyano-p-quinodimethane (TTF-TCNQ) using active termini of solution-formed sheaves has been introduced to form an extended assembly. We demonstrate for the first time, the creation of a large-area donor-acceptor assembly on the surface, which is practically very tedious, using a seeded, evaporation-assisted growth process. The excellent molecular ordering in this assembly is substantiated by its good electrical conductivity (~10⁻² S cm⁻¹). The on-surface assembly via both internally formed and externally added sheaf-like seeds open new pathways in supramolecular chemistry and device applications.

  4. Investigation on large-area fabrication of vivid shark skin with superior surface functions

    Science.gov (United States)

    Chen, Huawei; Zhang, Xin; Ma, Lingxi; Che, Da; Zhang, Deyuan; Sudarshan, T. S.

    2014-10-01

    Shark skin has attracted worldwide attention because of its superior drag reduction, antifouling performance induced from its unique surface morphology. Although the vivid shark skin has been fabricated by a bio-replicated micro-imprinting approach in previous studies and superior drag reduction effect has been validated in water tunnel, continuous large-area fabrication is still an obstacle to wide apply. In this paper, one novel bio-replication coating technology is proposed for large-area transfer of shark skin based on rapid UV curable paint. Apart from design of coating system, bio-replication accuracy of surface morphology was validated about 97% by comparison between shark skin template and coating surface morphology. Finally, the drag reduction and anti-fouling function of coating surface were tested in water tunnel and open algae pond respectively. Drag reduction rate of coating surface was validated about 12% higher and anti-fouling was proved to about hundred times ameliorate, all of which are more excellent than simple 2D riblet surface.

  5. Determination of the radon Concentration in underground water in selected areas in and around Kumasi

    International Nuclear Information System (INIS)

    Owusu, Seth Adjei

    2012-06-01

    Radon (Rn-222) is a radioactive noble gas of natural origin that may be found anywhere in soil, air and different types of water: surface, borehole, well and spring. It is worth to carry out surveys for the radon in water for radiation protection as well as for geological considerations. The research presenters here was carried out in selected towns in and around Kumasi for the determination of radon concentration in groundwater. The major towns from which samples were taken are , Mowire, Kronum, Aburaso, Medoma, Kenyase, Buokrom, Bomfa, Ayeduase, Kotei, Tikrom. All the samples are used for domestic purposes such as cooking, drinking, bathing and washing. Waters from boreholes and wells in the selected towns were sampled and the radon concentration level measured. The Roll’s method was used for the radon concentration analysis on all the 100 samples. The results shows that, the minimum radon concentration in groundwater was 13015.934 Bq/m3 and it was found at Bomfa, and the highest was found to be 964628.480 Bq/m3, recorded at Mowire. It is believed that this variation of levels is mainly due to the difference in rock type, soil type and geology of the area as well as the depth of the water samples. This information can be used to estimate the possible health hazards from radon in the selected towns in the future from environmental point of view. The data would promote public awareness related to risk of radon exposure. (au)

  6. 76 FR 80870 - Notice of Determination of Pest-Free Areas in Mendoza Province, Argentina

    Science.gov (United States)

    2011-12-27

    ... ;D=APHIS-2010-0032. The first commenter acknowledged Argentina's history of successful Medfly control...] Notice of Determination of Pest-Free Areas in Mendoza Province, Argentina AGENCY: Animal and Plant Health... Southern and Central Oases in the southern half of Mendoza Province in Argentina as pest-free areas for...

  7. 76 FR 56730 - Determination of Pest-Free Areas in Australia; Request for Comments

    Science.gov (United States)

    2011-09-14

    ... Health Inspection Service [Docket No. APHIS-2011-0088] Determination of Pest-Free Areas in Australia... are advising the public that we have received a request from the Government of Australia to recognize... has received a request from the Government of Australia to recognize new areas of that country as...

  8. Optimization of operating variables for production of ultra-fine talc in a stirred mill. Specific surface area investigations

    Directory of Open Access Journals (Sweden)

    Toraman Oner Yusuf

    2016-01-01

    Full Text Available Due to its properties such as chemical inertness, softness, whiteness, high thermal conductivity, low electrical conductivity and adsorption properties talc has wide industrial applications in paper, cosmetics, paints, polymer, ceramics, refractory materials and pharmaceutical. The demand for ultra-fine talc is emerging which drives the mineral industry to produce value added products. In this study, it was investigated how certain grinding parameters such as mill speed, ball filling ratio, powder filling ratio and grinding time of dry stirred mill affect grindability of talc ore (d97=127 μm. A series of laboratory experiments using a 24 full factorial design was conducted to determine the optimal operational parameters of a stirred mill in order to minimize the specific surface area. The main and interaction effects on the volume specific surface area (SV, m2.cm−3 of the ground product were evaluated using the Yates analysis. Under the optimal conditions at the stirrer speed of 600 rpm, grinding time of 20 min, sample mass of 5% and ball ratio of 70%, the resulting talc powder had larger volume specific surface area (i.e., 3.48 m2.cm−3 than the starting material (i.e., 1.84 m2.cm−3.

  9. Geoid determination in the coastal areas of the Gulf of Mexico

    Science.gov (United States)

    Song, HongZhi

    continuous map of gravity anomalies and a continuous map of gravity by using spatial interpolation methods and to evaluate errors; 2) to solve the Laplace boundary value problem and evaluate errors; 3) to evaluate precision of the local geoid by using geospatial statistical tools and numerical techniques. This dissertation investigates modeling of the geoid, especially the gravimetric equipotential surface that approximates mean sea level, in the coastal areas of the Gulf of Mexico as well as errors in the geoid determination. The document begins with Chapter 1 which introduces the study of this dissertation. Different models of kriging are used to determine the precision of the geoid based on the free-air gravity anomalies data supplied by United States Naval Research Laboratory and the airborne gravity data provided by the U.S. National Geodetic Survey, which can be found in Chapters 2 and 3. Research in Chapters 2 shows that more precise evaluation of errors in gravity anomalies can be achieved by using different models of kriging. Results from Chapters 2 and 3 show that ordinary kriging with the stable semivariogram model provide better predictions. Research results from Chapter 3 provide estimation of maximum possible errors in the calculation of the geoid undulation. The dissertation also investigates behavior of gravity equipotential surfaces around coastal lines and its impact on the geoid evaluation. Chapters 4 and 5 are about evaluation of errors in the Dirichlet problem for calculation of gravity potential with uncertain boundary and boundary values has been achieved by solving the Laplace equation by means of separation of variables. Research has provided a theoretical model in Chapter 4 to estimate very small changes in gravimetric potential relative to the coast. Maximum possible error in the solution of Direchlet problem is determined in Chapter 5. Maximum possible error depends on the errors of boundary values and the precision of the boundary itself. Chapter

  10. Modelling of particulate matter pollution (PM10) over the Etang de Berre area Determination of areas of homogeneous pollution

    International Nuclear Information System (INIS)

    Brocheton, F.; Poulet, D.; Mesbah, B.; Hourdin, G.

    2010-01-01

    AIRFOBEP is the association in charge of the air quality monitoring in the Etang de Berre area. AIRFOBEP is managing a network of ten sensors to monitor the PMI (particulate matter index) particulate pollution. This network is updated once a year according to the Air Quality Monitoring Plan (PSQA). Optimizing this network needs to know how the particulate pollution is distributed in the area. In other words, to determine the limits of homogeneous zones of PM 10 pollution. The aim of the project presented in this article is to produce a map of homogeneous zones of PM 10 pollution in the Etang de Berre area. The project was carried out in two steps: - PM 10 atmospheric dispersion modeling, using a ADMS-URBAN software, - Statistic classification, based on the well known Hierarchical Ascending Classification (HAC) technique. Results of the atmospheric dispersion modeling was namely adjusted using an original technique for the 'background PM 10 pollution' computation. Good performances have been obtained when comparing modeling and measurements data. Finally, a set of five homogeneous zones was found to well describe the PM 10 pollution level distribution in the Etang de Berre area. (author)

  11. Burning velocity and flame surface area in high Karlovitz number flames

    Science.gov (United States)

    Lapointe, Simon; Cheng, Lionel; Blanquart, Guillaume

    2017-11-01

    Accurate knowledge of the burning velocity of turbulent flames is of importance for many combustion devices. For low Karlovitz number flames, Damkohler proposed that the ratio of turbulent to laminar flame speed is proportional to the ratio of turbulent to laminar flame surface area. In recent DNS studies, it has been observed that Damkolher's scaling for low Karlovitz number flames still holds for high Karlovitz number flames. However, recent experimental studies have reported notable differences between global burning velocities and flame surface area measurements. In this work, the numerical and experimental results are further analyzed to explain the apparent contradiction. Emphasis is placed on identifying and quantifying potential experimental limitations at high Karlovitz numbers. More specifically, experimental flame surface measurements typically use binarized PLIF images. These images are two-dimensional and their resolution is limited by that of the PLIF system. The implications of using a two-dimensional iso-contour and the effects of the image resolution are assessed through post-processing of DNS datasets. Furthermore, the effects of integral length scale, Karlovitz number, and differential diffusion on the flame surface area are considered separately.

  12. Use of thermal inertia determined by HCMM to predict nocturnal cold prone areas in Florida

    Science.gov (United States)

    Allen, L. H., Jr. (Principal Investigator)

    1983-01-01

    Pairs of HCMM day-night thermal infrared (IR) data were selected during the 1978-79 winter to examine patterns of surface temperature and thermal inertia (TI) of peninsular Florida. The GOES and NOAA-6 thermal IR, as well as National Climatic Center temperatures and rainfall, were also used. The HCMM apparent thermal inertia (ATI) images closely corresponded to the general soil map of Florida, based on soil drainage classes. Areas with low ATI overlay well-drained soils, such as deep sands and drained organic soils, whereas with high ATI overlay areas with wetlands and bodies of water. The HCMM ATI images also corresponded well with GOES-detected winter nocturnal cold-prone areas. Use of HCMM data with Carlson's energy balance model showed both high moisture availability (MA) and high thermal inertia (TI) of wetland-type surfaces and low MA and low TI of upland, well-drained soils. Since soil areas with low TI develop higher temperatures during the day, then antecedent patterns of highest maximum daytime surface temperature can also be used to predict nocturnal cold-prone areas in Florida.

  13. Area Estimation of Deep-Sea Surfaces from Oblique Still Images.

    Directory of Open Access Journals (Sweden)

    Frederico Carvalho Dias

    Full Text Available Estimating the area of seabed surfaces from pictures or videos is an important problem in seafloor surveys. This task is complex to achieve with moving platforms such as submersibles, towed or remotely operated vehicles (ROV, where the recording camera is typically not static and provides an oblique view of the seafloor. A new method for obtaining seabed surface area estimates is presented here, using the classical set up of two laser devices fixed to the ROV frame projecting two parallel lines over the seabed. By combining lengths measured directly from the image containing the laser lines, the area of seabed surfaces is estimated, as well as the camera's distance to the seabed, pan and tilt angles. The only parameters required are the distance between the parallel laser lines and the camera's horizontal and vertical angles of view. The method was validated with a controlled in situ experiment using a deep-sea ROV, yielding an area estimate error of 1.5%. Further applications and generalizations of the method are discussed, with emphasis on deep-sea applications.

  14. Nanotechnological Advances in Catalytic Thin Films for Green Large-Area Surfaces

    Directory of Open Access Journals (Sweden)

    Suzan Biran Ay

    2015-01-01

    Full Text Available Large-area catalytic thin films offer great potential for green technology applications in order to save energy, combat pollution, and reduce global warming. These films, either embedded with nanoparticles, shaped with nanostructuring techniques, hybridized with other systems, or functionalized with bionanotechnological methods, can include many different surface properties including photocatalytic, antifouling, abrasion resistant and mechanically resistive, self-cleaning, antibacterial, hydrophobic, and oleophobic features. Thus, surface functionalization with such advanced structuring methods is of significance to increase the performance and wide usage of large-area thin film coatings specifically for environmental remediation. In this review, we focus on methods to increase the efficiency of catalytic reactions in thin film and hence improve the performance in relevant applications while eliminating high cost with the purpose of widespread usage. However, we also include the most recent hybrid architectures, which have potential to make a transformational change in surface applications as soon as high quality and large area production techniques are available. Hence, we present and discuss research studies regarding both organic and inorganic methods that are used to structure thin films that have potential for large-area and eco-friendly coatings.

  15. Quantitative comparison of mathematical models to measure surface area of canine teeth prepared to receive full veneer crowns in dogs

    Directory of Open Access Journals (Sweden)

    Caitlyn eCollins

    2015-09-01

    Full Text Available Objective: This study was performed in order to determine if mathematical modeling of the canine teeth in dogs could be utilized to provide an accurate and reliable estimation of crown surface area that could be used in both a research and clinical setting.Materials and methods: Actual surface area (aSA calculations for 32 stone dies of clinical crown preparations were acquired utilizing a tridimensional (3D laser scanner and 3D computer-aided design and manufacturing (CAD/CAM software applications. These calculations were used as a control. Seventeen unique mathematical models from 8 geometric shapes were used to calculate estimated surface area (eSA of each stone die. Linear association and agreement between eSA and aSA calculations were assessed with multiple statistical methods. Results: All methods of eSA showed a significant linear association with aSA. Five of the mathematical models [right elliptical frustum (H3, right elliptical cone (G3, right pyramidal cone (A3, right circular frustum (F2 and right circular cone (E1] were superior to the other 12 models.Conclusions: The H3 mathematical model based on the right elliptical frustum provided the most accurate estimate of crown surface area of dog teeth. However, H3 requires the use of laser scans and a 3D CAD software program. As a result, this model would be recommended for research applications. The E1 mathematical model was similar in accuracy to H3 and, given it requires only two measurements and a comparatively simple equation for calculation, this method would be recommended for clinical chair-side use.

  16. The reliability of three psoriasis assessment tools: Psoriasis area and severity index, body surface area and physician global assessment.

    Science.gov (United States)

    Bożek, Agnieszka; Reich, Adam

    2017-08-01

    A wide variety of psoriasis assessment tools have been proposed to evaluate the severity of psoriasis in clinical trials and daily practice. The most frequently used clinical instrument is the psoriasis area and severity index (PASI); however, none of the currently published severity scores used for psoriasis meets all the validation criteria required for an ideal score. The aim of this study was to compare and assess the reliability of 3 commonly used assessment instruments for psoriasis severity: the psoriasis area and severity index (PASI), body surface area (BSA) and physician global assessment (PGA). On the scoring day, 10 trained dermatologists evaluated 9 adult patients with plaque-type psoriasis using the PASI, BSA and PGA. All the subjects were assessed twice by each physician. Correlations between the assessments were analyzed using the Pearson correlation coefficient. Intra-class correlation coefficient (ICC) was calculated to analyze intra-rater reliability, and the coefficient of variation (CV) was used to assess inter-rater variability. Significant correlations were observed among the 3 scales in both assessments. In all 3 scales the ICCs were > 0.75, indicating high intra-rater reliability. The highest ICC was for the BSA (0.96) and the lowest one for the PGA (0.87). The CV for the PGA and PASI were 29.3 and 36.9, respectively, indicating moderate inter-rater variability. The CV for the BSA was 57.1, indicating high inter-rater variability. Comparing the PASI, PGA and BSA, it was shown that the PGA had the highest inter-rater reliability, whereas the BSA had the highest intra-rater reliability. The PASI showed intermediate values in terms of interand intra-rater reliability. None of the 3 assessment instruments showed a significant advantage over the other. A reliable assessment of psoriasis severity requires the use of several independent evaluations simultaneously.

  17. Use of thermal inertia determined by HCMM to predict nocturnal cold prone areas in Florida. [The Everglades agricultural area, Lake Okeechobee, and the Suwanee River basin

    Science.gov (United States)

    Allen, L. H., Jr. (Principal Investigator); Chen, E.; Martsolf, J. D.; Jones, P. H.

    1981-01-01

    Transparencies, prints, and computer compatible tapes of temperature differential and thermal inertia for the winter of 1978 to 1979 were obtained. Thermal inertial differences in the South Florida depicted include: drained organic soils of the Everglades agricultural area, undrained organic soils of the managed water conservation areas of the South Florida water management district, the urbanized area around Miami, Lake Okeechobee, and the mineral soil west of the Everglades agricultural area. The range of wetlands and uplands conditions within the Suwanee River basin was also identified. It is shown that the combination of wetlands uplands surface features of Florida yield a wide range of surface temperatures related to wetness of the surface features.

  18. A Study of Impermeable Surfaces in the Greater Washington, D.C. Area

    OpenAIRE

    O'Connor, Mary; Chase-Walsh, Sarah; Cerquiera, Stephen

    2014-01-01

    The Washington D.C. area, like many cities, is covered with impermeable surfaces. With millions of cars on the roads every year, runoff is a major problem for the Potomac and the Anacostia rivers, which both empty into the Chesapeake Bay. Large buildings, constant construction, and an extensive highway system contribute to and expedite runoff. We will examine the amount of change in impermeable surfaces throughout the years and the effect runoff has on these two rivers. We also want to look a...

  19. The triazine-based porous organic polymer: Novel synthetic strategy for high specific surface area

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Kuen [Dept. of Chemistry, Hankuk University of Foreign Studies, Yongin (Korea, Republic of)

    2017-02-15

    A new type of microporous polymer has been successively synthesized via a simple polycondensation reaction with the 2,4-diaminotriazine moiety and dianhydride monomer. Diaminotriazine moieties in M1 especially can provide effective branching sites, resulting in high surface areas up to 1150 m{sup 2} /g. In addition, the specific pore structure of the polyimide POP in its solid state can be modified by the surface activation method. Therefore, it can be expected that the resulting material will be a promising candidate for gas storage, and with this synthetic strategy, various type of derivatives will also be optimized.

  20. Impervious Surfaces Alter Soil Bacterial Communities in Urban Areas: A Case Study in Beijing, China.

    Science.gov (United States)

    Hu, Yinhong; Dou, Xiaolin; Li, Juanyong; Li, Feng

    2018-01-01

    The rapid expansion of urbanization has caused land cover change, especially the increasing area of impervious surfaces. Such alterations have significant effects on the soil ecosystem by impeding the exchange of gasses, water, and materials between soil and the atmosphere. It is unclear whether impervious surfaces have any effects on soil bacterial diversity and community composition. In the present study, we conducted an investigation of bacterial communities across five typical land cover types, including impervious surfaces (concrete), permeable pavement (bricks with round holes), shrub coverage ( Buxus megistophylla Levl. ), lawns ( Festuca elata Keng ex E. Alexeev ), and roadside trees ( Sophora japonica Linn. ) in Beijing, to explore the response of bacteria to impervious surfaces. The soil bacterial communities were addressed by high-throughput sequencing of the bacterial 16S rRNA gene. We found that Proteobacteria , Actinobacteria , Acidobacteria , Bacteroidetes , Chloroflexi , and Firmicutes were the predominant phyla in urban soils. Soil from impervious surfaces presented a lower bacterial diversity, and differed greatly from other types of land cover. Soil bacterial diversity was predominantly affected by Zn, dissolved organic carbon (DOC), and soil moisture content (SMC). The composition of the bacterial community was similar under shrub coverage, roadside trees, and lawns, but different from beneath impervious surfaces and permeable pavement. Variance partitioning analysis showed that edaphic properties contributed to 12% of the bacterial community variation, heavy metal pollution explained 3.6% of the variation, and interaction between the two explained 33% of the variance. Together, our data indicate that impervious surfaces induced changes in bacterial community composition and decrease of bacterial diversity. Interactions between edaphic properties and heavy metals were here found to change the composition of the bacterial community and diversity

  1. Impervious Surfaces Alter Soil Bacterial Communities in Urban Areas: A Case Study in Beijing, China

    Directory of Open Access Journals (Sweden)

    Yinhong Hu

    2018-02-01

    Full Text Available The rapid expansion of urbanization has caused land cover change, especially the increasing area of impervious surfaces. Such alterations have significant effects on the soil ecosystem by impeding the exchange of gasses, water, and materials between soil and the atmosphere. It is unclear whether impervious surfaces have any effects on soil bacterial diversity and community composition. In the present study, we conducted an investigation of bacterial communities across five typical land cover types, including impervious surfaces (concrete, permeable pavement (bricks with round holes, shrub coverage (Buxus megistophylla Levl., lawns (Festuca elata Keng ex E. Alexeev, and roadside trees (Sophora japonica Linn. in Beijing, to explore the response of bacteria to impervious surfaces. The soil bacterial communities were addressed by high-throughput sequencing of the bacterial 16S rRNA gene. We found that Proteobacteria, Actinobacteria, Acidobacteria, Bacteroidetes, Chloroflexi, and Firmicutes were the predominant phyla in urban soils. Soil from impervious surfaces presented a lower bacterial diversity, and differed greatly from other types of land cover. Soil bacterial diversity was predominantly affected by Zn, dissolved organic carbon (DOC, and soil moisture content (SMC. The composition of the bacterial community was similar under shrub coverage, roadside trees, and lawns, but different from beneath impervious surfaces and permeable pavement. Variance partitioning analysis showed that edaphic properties contributed to 12% of the bacterial community variation, heavy metal pollution explained 3.6% of the variation, and interaction between the two explained 33% of the variance. Together, our data indicate that impervious surfaces induced changes in bacterial community composition and decrease of bacterial diversity. Interactions between edaphic properties and heavy metals were here found to change the composition of the bacterial community and

  2. Heavy metal contamination of surface soil in electronic waste dismantling area: site investigation and source-apportionment analysis.

    Science.gov (United States)

    Jinhui Li; Huabo Duan; Pixing Shi

    2011-07-01

    The dismantling and disposal of electronic waste (e-waste) in developing countries is causing increasing concern because of its impacts on the environment and risks to human health. Heavy-metal concentrations in the surface soils of Guiyu (Guangdong Province, China) were monitored to determine the status of heavy-metal contamination on e-waste dismantling area with a more than 20 years history. Two metalloids and nine metals were selected for investigation. This paper also attempts to compare the data among a variety of e-waste dismantling areas, after reviewing a number of heavy-metal contamination-related studies in such areas in China over the past decade. In addition, source apportionment of heavy metal in the surface soil of these areas has been analysed. Both the MSW open-burning sites probably contained invaluable e-waste and abandoned sites formerly involved in informal recycling activities are the new sources of soil-based environmental pollution in Guiyu. Although printed circuit board waste is thought to be the main source of heavy-metal emissions during e-waste processing, requirement is necessary to soundly manage the plastic separated from e-waste, which mostly contains heavy metals and other toxic substances.

  3. Definition and experimental determination of a soil-water retention surface

    OpenAIRE

    Salager, S.; El Youssoufi, M. S.; Saix, C.

    2010-01-01

    International audience; This paper deals with the definition and determination methods of the soil-water retention surface (SWRS), which is the tool used to present the hydromechanical behaviour of soils to highlight both the effect of suction on the change in water and total volumes and the effect of deformation with respect to the water retention capability. An experimental method is introduced to determine the SWRS and applied to a clayey silty sand. The determination of this surface is ba...

  4. Gross alpha and gross beta determination in surface and groundwater water by liquid scintillation counting (LSC)

    Energy Technology Data Exchange (ETDEWEB)

    Faria, Ligia S.; Moreira, Rubens M., E-mail: ligsfaria@gmail.com, E-mail: rubens@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    The present study has used 40 samples of groundwater and surface water collected at four different sites along the period of one year in Brumadinho and Nova Lima, two municipalities in the State of Minas Gerais, Brazil, as part of a more extensive study aiming at determination of the natural radioactivity in the water used for domestic use. These two sites are inside an Environmental Protection Area is located in a region of very intensive iron ore exploration. In addition of mineral resources, the region has a geological characteristic that includes quartzitic conglomerates associated with uranium. Radioactivity levels were determined via liquid scintillation counting (LSC), a fast and high counting efficiency method that can be advantageously employed to determine gross alpha and gross beta activity in liquid samples. Previously to gross alpha and gross beta counting the samples were acidified with concentrated HNO{sub 3} in the field. The technique involved a pre-concentration of the sample to obtain a low detection limit. Specific details of the employed methodology are commented. The results showed that concentrations of gross alpha natural activity and gross beta values ranged from less than the detection limit of the equipment (0.03 Bq.L{sup -1}) to 0.275 ± 0.05 Bq.L{sup -1} for gross alpha. As regards gross beta, all samples were below the limit of detection. (author)

  5. Phase contrast imaging reveals low lung volumes and surface areas in the developing marsupial.

    Directory of Open Access Journals (Sweden)

    Shannon J Simpson

    Full Text Available Marsupials are born with immature lungs when compared to eutherian mammals and rely, to various extents, on cutaneous gas exchange in order to meet metabolic requirements. Indeed, the fat-tailed dunnart is born with lungs in the canalicular stage of development and relies almost entirely on the skin for gas exchange at birth; consequently undergoing the majority of lung development in air. Plane radiographs and computed tomography data sets were acquired using phase contrast imaging with a synchrotron radiation source for two marsupial species, the fat-tailed dunnart and the larger tammar wallaby, during the first weeks of postnatal life. Phase contrast imaging revealed that only two lung sacs contain air after the first hour of life in the fat-tailed dunnart. While the lung of the tammar wallaby was comparatively more developed, both species demonstrated massive increases in air sac number and architectural complexity during the postnatal period. In addition, both the tammar wallaby and fat-tailed dunnart had lower lung volumes and parenchymal surface areas than were expected from morphometrically determined allometric equations relating these variables to body mass during the neonatal period. However, lung volume is predicted to scale with mass as expected after the neonatal marsupial reaches a body mass of ∼1 g and no longer relies on the skin for gas exchange. Decreased lung volume in the marsupial neonate further supports the maxim that cutaneous gas exchange occurs in the marsupial neonate because the respiratory apparatus is not yet capable of meeting the gas exchange requirements of the newborn.

  6. Can We Trust Real Time Measurements of Lung Deposited Surface Area Concentrations in Dust from Powder Nanomaterials?

    DEFF Research Database (Denmark)

    Levin, Marcus; Witschger, Olivier; Bau, Sebastien

    2016-01-01

    A comparison between various methods for real-time measurements of lung deposited surface area (LDSA) using spherical particles and powder dust with specific surface area ranging from 0.03 to 112 m2 g-1 was conducted. LDSA concentrations measured directly using Nanoparticle Surface Area Monitor...... (NSAM) and Aerotrak and were compared to LDSA concentrations recalculated from size distribution measurements using Electrical Low Pressure Impactor (ELPI) and Fast Mobility Particle Sizer (FMPS). FMPS and ELPI measurements were also compared to dust surface area concentrations estimated from...... gravimetrical filter measurements and specific surface areas. Measurement of LDSA showed very good correlation in measurements of spherical particles (R2 > 0.97, Ratio 1.0 to 1.04). High surface area nanomaterial powders showed a fairly reliable correlation between NSAM and Aerotrak (R2 0...

  7. Use of surface area computations to describe atom-atom interactions.

    Science.gov (United States)

    de La Cruz, X; Calvo, M

    2001-06-01

    Accessible surface (ASA) and atomic contact (ACA) areas are powerful tools for protein structure analysis. However, their use for analysis purposes could be extended if a relationship between them and protein stability could be found. At present, this is the case only for ASAs, which have been used to assess the contribution of the hydrophobic effect to protein stability. In the present work we study whether there is a relationship between atomic contact areas and the free energy associated to atom-atom interactions. We utilise a model in which the contribution of atomic interactions to protein stability is expressed as a linear function of the accessible surface area buried between atom pairs. We assess the validity of this hypothesis, using a set of 124 lysozyme mutants (Matthews, 1995, Adv Protein Chem, 249-278) for which both the X-ray structure and the experimental stability are known. We tested this assumption for residue representations with increasing numbers of atom types. Our results indicate that for simple residue representations, with only 4 to 5 atom types, there is not a clear linear relationship between stability and buried accessible area. However, this relationship is observed for representations with 6 to 9 atom types, where gross heterogeneities in the atom type definition are eliminated. Finally, we also study a version of the linear model in which the atom- atom interactions are represented utilising a simple function for the buried accessible area, which may be useful for protein structure prediction studies.

  8. [Distribution Characteristics of Fluoroquinolones Antibiotics in Surface Water and Groundwater from Typical Areas in A City].

    Science.gov (United States)

    Cui, Ya-feng; He, Jiang-tao; Su, Si-hui; Yang, Lei; Qiao, Xiao-cui

    2015-11-01

    In order to investigate the characteristics of 5 typical kinds of fluoroquinolones (FQs) pollution in waters from a city, surface water and groundwater samples from main drainage rivers and typical areas were collected, respectively. The conventional test and FQs concentrations analysis of the water samples were conducted. The results showed the concentration and composition of FQs in groundwater differed substantially from those in surface water. The average concentration of FQs in surface water was 789.1 ng x L(-1) with the main components of ofloxacin (OFL) and lomefloxacin (LOM). This value was higher than the average concentration of FQs in groundwater: 342.7 ng x L(-1) with the main components of norfloxacin (NOR) and lomefloxacin (LOM). The enrofloxacin (ENR) exhibited relatively lower levels in both surface water and groundwater as compared to others. The highest FQs concentrations in surface water were found in trenches, followed by tributaries and the main stream. For groundwater, FQs concentrations were relatively higher in the sewage riverside. A decreasing trend of FQs concentration was monitored with the increasing distance of sampling points to the drainage rivers and all components mentioned above showed similar changing trends. The results of this study preliminarily indicated that FQs in groundwater along the riverside probably came from the surface water.

  9. Phenomenological study of aerosol dry deposition in urban area: surface properties, turbulence and local meteorology influences

    International Nuclear Information System (INIS)

    Roupsard, P.

    2013-01-01

    Aerosol dry deposition is not much known for urban areas due to the lack of data. Knowledge on this phenomenon is necessary to understand pollutant fluxes in cities and to estimate inhabitant exposition to ionizing radiation of radioactive aerosols. A data providing could enable to enhance dry deposition models for these areas. An original experimental approach is performed to study submicron aerosol dry deposition on urban surfaces. Wind tunnel coupled to in situ experiments give results to study different physical phenomenon governing dry deposition. Dry deposition velocities are measured using aerosol tracers. These data are associated to turbulent and meteorological measured conditions. This database permits to classify the principal physical phenomenon for each experiment type. Finally, different phenomenon must be considered for chronic and acute exposition of urban surfaces to atmospheric particles. (author)

  10. Effect of perfusate hematocrit on urea permeability-surface area in isolated dog lung

    International Nuclear Information System (INIS)

    Parker, R.E.; Roselli, R.J.; Haselton, F.R.; Harris, T.R.

    1986-01-01

    Seven dog lower left lung lobes were statically inflated and perfused at a constant rate for each lobe with a perfusate in which the hematocrit was altered over a wide range. The permeability-surface area of urea was calculated from multiple indicator dilution curves using two separate injectates for each hematocrit level. One injectate contained only 125 I-albumin as the vascular reference tracer and the other contained both 51 Cr-erythrocytes and 125 I-albumin as the vascular reference tracers; both contained [ 14 C]urea as the permeating tracer. The results strongly indicate that the phenomenon of erythrocyte trapping of urea does not affect the calculation of urea permeability-surface area product provided the appropriate albumin-erythrocyte composite reference tracer is utilized in its calculation

  11. Determinants of SME location in a suburban area: Evidence from the Gdańsk–Gdynia–Sopot Metropolitan Area

    Directory of Open Access Journals (Sweden)

    Justyna Martyniuk-Pęczek

    2017-06-01

    Full Text Available Given the importance of small and medium enterprises (SMEs in the European economy, it is essential to have adequate information about the various factors that determine their choice of location. However, the size of a company is often an aspect not covered in theoretical studies and empirical research on industrial locations and urban planning. This article examines the place of residence as a stimulator of SME development in suburbs. Multidisciplinary research carried out in the Gdańsk–Gdynia–Sopot Metropolitan Area, known as the Tricity, confirms this trend. The location determinants of SMEs in suburban areas were identified using a questionnaire. The survey was conducted in 251 enterprises located in seven municipalities with the highest suburbanisation rates within the Tricity. The study confirms that the municipalities characterised by the highest intensity of suburbanisation processes have higher business activity than other municipalities. Location decisions were largely made by business owners in line with behavioural theory. This means that SME owners more often consider personal factors than cost or demand factors. From the perspective of an entrepreneur, living conditions, the quality of public space, education and healthcare are significant.

  12. Surface area of lactose and lactose granulates on consolidation and compaction

    OpenAIRE

    Riepma, Klaas Alouis

    1993-01-01

    This dissertation discusses the effect of short time storage at different conditions on the strength and the specific BET surface area of lactose tablets. In addition, some aspects are studied of the consolidation and compaction properties of crystalline lactose fractions in heterogeneous systems. The crystalline lactose types used are: a-lactose monohydrate, anhydrous a-lactose, crystalline B-lactose and roller dried B-lactose. ... Zie: Summary

  13. Synthesis of high-surface-area spinel-type MgAl2O4 nanoparticles ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 40; Issue 1. Synthesis of high-surface-area spinel-type MgAl 2 O 4 nanoparticles by [Al(sal) 2 (H 2 O) 2 ] 2 [Mg(dipic) 2 ] and [Mg(H 2 O) 6 ][Al(ox) 2 (H 2 O) 2 ] 2 ·5H 2 O: influence of inorganic precursor type. Volume 40 Issue 1 February 2017 pp 45-53 ...

  14. Sensitivity analysis of the surface water- groundwater interaction for the sandy area of the Netherlands

    OpenAIRE

    Gomez del Campo, E.; Jousma, G.; Massop, H.T.L.

    1993-01-01

    The "Sensitivity Analysis of the Surface Water- Groundwater Interaction for the Sandy Area of the Netherlands" was carried out in the framework of a bilateral research project in support of the implementation of a nationwide geohydrological information system (REGIS) in the Netherlands. This project, conducted in cooperation between the TNO Institute for Applied Scientific Research (IGG-TNO) and !he Winand Staring Centre for Integrated Land, Soil and Water Research (SC-DLO), is aimed at defin...

  15. Formula and Scale for Body Surface Area Estimation in High-Risk Infants

    OpenAIRE

    Ahn, Youngmee

    2010-01-01

    Advances in medical technology and the health sciences have lead to a rapid increase in the prevalence and morbidity of high-risk infants with chronic or permanent sequels such as the birth of early preterm infants. A suitable formula is therefore needed for body surface area (BSA) estimation for high-risk infants to more accurately devise therapeutic regimes in clinical practice. A cohort study involving 5014 high-risk infants was conducted to develop a suitable formula for estimating BSA us...

  16. High-Surface-Area Porous Platinum Electrodes for Enhanced Charge Transfer

    OpenAIRE

    Hu Yelin; Yella Aswani; Guldin Stefan; Schreier Marcel; Stellacci Francesco; Grätzel Michael; Stefik Morgan

    2014-01-01

    Cobalt based electrolytes are highly tunable and have pushed the limits of dye sensitized solar cells enabling higher open circuit voltages and new record effi ciencies. However the performance of these electrolytes and a range of other electrolytes suffer from slow electron transfer at platinum counter electrodes. High surface area platinum would enhance catalysis but pure platinum structures are too expensive in practice. Here a material effi cient host guest architecture is developed that ...

  17. n-Alkylamine-assisted preparation of a high surface area vanadyl phosphate/tetraethylorthosilicate nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, João Paulo L., E-mail: billbrujah@yahoo.com.br [Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, SP 14040-901 (Brazil); Zampronio, Elaine C.; Oliveira, Herenilton P. [Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, SP 14040-901 (Brazil)

    2013-02-15

    Graphical abstract: CuK{sub α} X-ray diffraction patterns of the VP, VPOc, VPOcT, VPOcT200 and VPOcT500. Highlights: ► TEOS and octylamine incorporation into the VP was achieved by expanding the lamellar. ► The specific surface area increased from 15 m{sup 2} g{sup −1} in VP to 237 m{sup 2} g{sup −1} in VPOcT. ► The VPOcT exhibited thermal resistance up to 200 °C in air. ► Upon thermal treatment up to 500 °C, the surface area increased to 838 m{sup 2} g{sup −1}. -- Abstract: We have developed a vanadyl phosphate/tetraethylorthosilicate (VPO/TEOS) nanocomposite comprised of silicate chains interleaved with VPO layers, prepared by using an n-alkylamines such as octylamine as the structure directing agent. The nanocomposites were synthesized by reacting amine-intercalated vanadyl phosphate with tetraethylorthosilicate via the soft chemistry approach. The synthetic procedure encompassed the exfoliation of the layered vanadyl phosphate as well as the reorganization of this exfoliated solid into a mesostructured lamellar phase with the same V–P–O connectivity as in the original matrix. TEOS incorporation into the vanadyl phosphate was achieved by expanding the lamellar structure with n-alkylamine (Δd = 13 Å with n-octylamine). The specific surface area increased from 15 m{sup 2} g{sup −1} in the vanadyl phosphate matrix to 237 m{sup 2} g{sup −1} in VPOcT, and the isotherm curves revealed the characteristic hysteresis of mesoporous materials. Upon thermal treatment up to 500 °C, the surface area increased to 837 m{sup 2} g{sup −1}, which is suitable for catalytic purposes.

  18. Growth of Hierarchically Structured High-Surface Area Alumina on FeCrAl Alloy Wires

    Directory of Open Access Journals (Sweden)

    Chandni Rallan

    2013-01-01

    Full Text Available The formation of metastable alumina phases due to the oxidation of commercial FeCrAl alloy wires (0.5 mm thickness at various temperatures and time periods has been examined. Samples were isothermally oxidised in air using a thermogravimetric analyzer (TGA. The morphology of the oxidised samples was analyzed using an Electronic Scanning Electron Microscope (ESEM and X-ray on the surface analysis was done using an Energy Dispersive X-Ray (EDX analyzer. The technique of X-Ray Diffraction (XRD was used to characterize the phase of the oxide growth. The entire study showed that it was possible to grow high-surface area gamma alumina on the FeCrAl alloy wire surfaces when isothermally oxidised above 800°C over several hours.

  19. How Much Global Burned Area Can Be Forecast on Seasonal Time Scales Using Sea Surface Temperatures?

    Science.gov (United States)

    Chen, Yang; Morton, Douglas C.; Andela, Niels; Giglio, Louis; Randerson, James T.

    2016-01-01

    Large-scale sea surface temperature (SST) patterns influence the interannual variability of burned area in many regions by means of climate controls on fuel continuity, amount, and moisture content. Some of the variability in burned area is predictable on seasonal timescales because fuel characteristics respond to the cumulative effects of climate prior to the onset of the fire season. Here we systematically evaluated the degree to which annual burned area from the Global Fire Emissions Database version 4 with small fires (GFED4s) can be predicted using SSTs from 14 different ocean regions. We found that about 48 of global burned area can be forecast with a correlation coefficient that is significant at a p burning. Continental regions where burned area had a higher degree of predictability included equatorial Asia, where 92% of the burned area exceeded the correlation threshold, and Central America, where 86% of the burned area exceeded this threshold. Pacific Ocean indices describing the El Nino-Southern Oscillation were more important than indices from other ocean basins, accounting for about 1/3 of the total predictable global burned area. A model that combined two indices from different oceans considerably improved model performance, suggesting that fires in many regions respond to forcing from more than one ocean basin. Using OCI-burned area relationships and a clustering algorithm, we identified 12 hotspot regions in which fires had a consistent response to SST patterns. Annual burned area in these regions can be predicted with moderate confidence levels, suggesting operational forecasts may be possible with the aim of improving ecosystem management.

  20. [Distribution, surface and protected area of palm-swamps in Costa Rica and Nicaragua].

    Science.gov (United States)

    Serrano-Sandí, Juan; Bonilla-Murillo, Fabian; Sasa, Mahmood

    2013-09-01

    In Central America, palm swamps are known collectively as yolillales. These wetlands are usually dominated by the raffia palm Raphia taedigera, but also by the royal palm Manicaria saccifera and -in lower extensions- by the American oil palm Elaeis oleifera. The yolillales tend to be poor in woody species and are characteristic of regions with high rainfall and extensive hydroperiods, so they remain flooded most of the year. The dominance of large raffia palm leaves in the canopy, allow these environments to be distinguishable in aerial photographs, which consequently has helped to map them along most of their distribution. However, while maps depicting yolillales are available, the extent of their surface area, perimeter and connectivity remains poorly understood. This is particularly true for yolillales in Costa Rica and Nicaragua, countries that share a good proportion of palm dominated swaps in the Rio San Juan Basin. In addition, it is not known the actual area of these environments that is under any category of protection according to the conservation systems of both countries. As a first step to catalog yolillal wetlands in Costa Rica and Nicaragua, this paper evaluates cartographic maps to delineate yolillales in the region. A subsample of yolillales mapped in this study were visited and we geo-referenced them and evaluate the extent and condition of the swamp. A total of 110 883.2ha are classified as yolillales in Nicaragua, equivalent to 22% of wetland surface area recorded for that country (excluding the Cocibolca and Xolothn Lakes). In Costa Rica, 53 931.3ha are covered by these palm dominated swamps, which represent 16.24% of the total surface area covered by wetlands. About 47% of the area covered by yolillales in Nicaragua is under some category of protection, the largest extensions protected by Cerro Silva, Laguna Tale Sulumas and Indio Maiz Nature Reserves. In Costa Rica, 55.5% of the area covered by yolillal is located within protected areas

  1. Kilohertz Electrical Stimulation Nerve Conduction Block: Effects of Electrode Surface Area.

    Science.gov (United States)

    Patel, Yogi A; Kim, Brian S; Rountree, William S; Butera, Robert J

    2017-10-01

    Kilohertz electrical stimulation (KES) induces repeatable and reversible conduction block of nerve activity and is a potential therapeutic option for various diseases and disorders resulting from pathological or undesired neurological activity. However, successful translation of KES nerve block to clinical applications is stymied by many unknowns, such as the relevance of the onset response, acceptable levels of waveform contamination, and optimal electrode characteristics. We investigated the role of electrode geometric surface area on the KES nerve block threshold using 20- and 40-kHz current-controlled sinusoidal KES. Electrodes were electrochemically characterized and used to characterize typical KES waveforms and electrode charge characteristics. KES nerve block amplitudes, onset duration, and recovery of normal conduction after delivery of the KES were evaluated along with power requirements for effective KES nerve block. Results from this investigation demonstrate that increasing electrode geometric surface area provides for a more power-efficient KES nerve block. Reductions in block threshold by increased electrode surface area were found to be KES-frequency-dependent, with block thresholds and average power consumption reduced by greater than two times with 20-kHz KES waveforms and greater than three times for 40-kHz KES waveforms.

  2. Effect of Precipitation Conditions on the Specific Surface Area of Neptunium Oxide

    International Nuclear Information System (INIS)

    HILL, BENJAMINC.

    2004-01-01

    Neptunium oxalate was precipitated under nominal and bounding HB-Line flowsheet conditions. The nominal case represents expected normal HB-Line operation. The bounding case represents process flowsheet extremes that could occur which are anticipated to decrease particle size and increase surface area. The neptunium oxalate produced under bounding conditions was used to validate the effectiveness of HB-Line calcination conditions. The maximum specific surface area of the neptunium oxide (NpO2) used in gas generation testing was 5.34 m2/g. Experiments were conducted to verify that even under bounding precipitation conditions the SSA of NpO2 produced would remain within the range evaluated during gas generation testing. The neptunium oxalate from nominal and bounding precipitation conditions was calcined at 600 degrees Celsius and 625 degrees Celsius, respectively, to form NpO2. Samples from each batch of neptunium oxalate were calcined for one, two, or four hours. Results indicate that the SSA of NpO2 continues to decrease between one and four hours. After two hours of calcination at 625 degrees Celsius, the SSA of NpO2 from the bounding case meets the surface area requirements for limiting moisture uptake

  3. Detailed effects of particle size and surface area on 222Rn emanation of a phosphate rock.

    Science.gov (United States)

    Haquin, Gustavo; Yungrais, Zohar; Ilzycer, Danielle; Zafrir, Hovav; Weisbrod, Noam

    2017-12-01

    The dependency of radon emanation on soil texture was investigated using the closed chamber method. Ground phosphate rock with a large specific surface area was analyzed, and the presence of inner pores, as well as a high degree of roughness and heterogeneity in the phosphate particles, was found. The average radon emanation of the dry phosphate was 0.145 ± 0.016. The emanation coefficient was highest (0.169 ± 0.019) for the smallest particles (210 μm). The reduction rate followed an inverse power law. As expected, a linear dependence between the emanation coefficient and the specific surface area was found, being lower than predicted for the large specific surface area. This was most likely due to an increase in the embedding effect of radon atoms in adjacent grains separated by micropores. Results indicate that knowledge of grain radium distribution is crucial to making accurate emanation predictions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Preparation of high surface area and high conductivity polyaniline nanoparticles using chemical oxidation polymerization technique

    Science.gov (United States)

    Budi, S.; Yusmaniar; Juliana, A.; Cahyana, U.; Purwanto, A.; Imaduddin, A.; Handoko, E.

    2018-03-01

    In this work, polyaniline nanoparticles were synthesized using a chemical oxidation polymerization technique. The ammonium peroxydisulfate (APS)/aniline ratio, APS dropping time, and polymerization temperature were optimized to increase the surface area and conductivity of the polyaniline.The Fourier-transform infrared (FTIR) spectrum confirmed the formation of emeraldine salt polyaniline. X-ray diffraction (XRD) patterns indicated that amorphous and crystalline phases of the polyaniline were formed with crystallinity less than 40%. Scanning electron microscope (SEM) micrographs showed that the finest nanoparticles with uniform size distribution were obtained at the polymerization temperature of 0°C. A surface area analyzer (SAA) showed that the highest Brunauer-Emmett-Teller surface area (SBET ) of 42.14 m2/gwas obtained from an APS/aniline ratio of 0.75 with a dropping time of 0 s at a polymerization temperature of 0°C. A four-point probe measurement conducted at 75–300K indicated relatively high conductivity of the semiconductor characteristic of the polyaniline.

  5. Effects of acid treatment on the clay palygorskite: XRD, surface area, morphological and chemical composition

    Energy Technology Data Exchange (ETDEWEB)

    Xavier, Katiane Cruz Magalhaes; Santos, Maria do Socorro Ferreira dos; Santos, Maria Rita Morais Chaves; Oliveira, Marilia Evelyn Rodrigues; Osajima, Josy Antevelli; Silva Filho, Edson Cavalcanti da [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil); Carvalho, Maria Wilma Nunes Cordeiro, E-mail: edsonfilho@ufpi.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2014-08-15

    The palygorskite is an aluminum-magnesium silicate that has a fibrous morphology. Their physicochemical characteristics are the result of high surface area, porosity and thermal resistance which make it an attractive adsorbent. Its adsorption capacity can be increased through chemical reactions and/or heat treatments. The objective of this work is to verify the effects of acid activation on the palygorskite, treated with HCl at 90 °C at concentrations of 2, 4 and 6 mol L{sup -1} in 2 and 4 hours, with clay/acid solution ratio 1 g 10 mL{sup -1} and characterized by techniques: XRF, XRD and surface area. A significant increase in specific surface area was observed in the sample treated with HCl at the concentration 6 mol L{sup -1}. The changes were more pronounced at stricter concentrations of acidity, with decreasing intensity of reflection of the clay indicated in the XRD. These changes were confirmed in the XRF with the leaching of some oxides and with increasing concentration of SiO{sub 2}. (author)

  6. Relationship Between the Surface Area to Volume Ratio and Temperature across Geologic Time in Ostracods

    Science.gov (United States)

    Jackson, C.; Zaroff, S.; Heim, N. A.; Payne, J.

    2014-12-01

    In 1877 Joseph Allen proposed that endothermic terrestrial organisms would have lower surface area to volume ratios (SAVR) in colder climates and higher SAVRs in warmer climates. With a smaller surface area compared to volume, organisms can retain more heat in cold climates. We tested to see if this principle applied to ostracods, a type of ectothermic marine invertebrate. We hypothesised that Allen's rule applies to ostracods, as Allen's rule has been demonstrated in frogs (Alho 2011), which are also ectotherms . We used the linear dimensions of the three major carapace axes of ostracod holotypes to estimate the SAVR. We compared ostracod SAVRs with paleotemperatures from Royer et al. (2004). We found that there was a correlation between surface area and temperature; it is a small, but statistically significant correlation (adj. R2=0.0167). This means that as temperature increased, the SAVR also increased. We also found a negative correlation between ostracod SAVR to geologic time(adj. R2=0.0114), which shows us that as time has gone on, ostracod SAVR has decreased. We then plotted the correlation coefficient of SAVR to temperature over geologic time to explore trends in the strength of Allen's rule. For most of time there was no relationship but during the Devonian, Allen's Rule did explain the trend. In short, temperature does explain some of the correlation between the SAVR and temperature, but it is likely there were other environmental factors affecting this relationship.

  7. Mineral paragenesis on Mars: The roles of reactive surface area and diffusion.

    Science.gov (United States)

    Fairén, Alberto G; Gil-Lozano, Carolina; Uceda, Esther R; Losa-Adams, Elisabeth; Davila, Alfonso F; Gago-Duport, Luis

    2017-09-01

    Geochemical models of secondary mineral precipitation on Mars generally assume semiopen systems (open to the atmosphere but closed at the water-sediment interface) and equilibrium conditions. However, in natural multicomponent systems, the reactive surface area of primary minerals controls the dissolution rate and affects the precipitation sequences of secondary phases, and simultaneously, the transport of dissolved species may occur through the atmosphere-water and water-sediment interfaces. Here we present a suite of geochemical models designed to analyze the formation of secondary minerals in basaltic sediments on Mars, evaluating the role of (i) reactive surface areas and (ii) the transport of ions through a basalt sediment column. We consider fully open conditions, both to the atmosphere and to the sediment, and a kinetic approach for mineral dissolution and precipitation. Our models consider a geochemical scenario constituted by a basin (i.e., a shallow lake) where supersaturation is generated by evaporation/cooling and the starting point is a solution in equilibrium with basaltic sediments. Our results show that cation removal by diffusion, along with the input of atmospheric volatiles and the influence of the reactive surface area of primary minerals, plays a central role in the evolution of the secondary mineral sequences formed. We conclude that precipitation of evaporites finds more restrictions in basaltic sediments of small grain size than in basaltic sediments of greater grain size.

  8. Surface water areas significantly impacted 2014 dengue outbreaks in Guangzhou, China

    International Nuclear Information System (INIS)

    Tian, Huaiyu; Huang, Shanqian; Zhou, Sen; Bi, Peng; Yang, Zhicong; Li, Xiujun; Chen, Lifan; Cazelles, Bernard; Yang, Jing; Luo, Lei; Jing, Qinlong; Yuan, Wenping; Pei, Yao; Sun, Zhe; Yue, Tianxiang; Kwan, Mei-Po

    2016-01-01

    Dengue transmission in urban areas is strongly influenced by a range of biological and environmental factors, yet the key drivers still need further exploration. To better understand mechanisms of environment–mosquito–urban dengue transmission, we propose an empirical model parameterized and cross-validated from a unique dataset including viral gene sequences, vector dynamics and human dengue cases in Guangzhou, China, together with a 36-year urban environmental change maps investigated by spatiotemporal satellite image fusion. The dengue epidemics in Guangzhou are highly episodic and were not associated with annual rainfall over time. Our results indicate that urban environmental changes, especially variations in surface area covered by water in urban areas, can substantially alter the virus population and dengue transmission. The recent severe dengue outbreaks in Guangzhou may be due to the surge in an artificial lake construction, which could increase infection force between vector (mainly Aedes albopictus) and host when urban water area significantly increased. Impacts of urban environmental change on dengue dynamics may not have been thoroughly investigated in the past studies and more work needs to be done to better understand the consequences of urbanization processes in our changing world. - Highlights: • Urban dengue outbreak is associated with water area in Guangzhou, 1978–2014. • Surface water area can alter population size of dengue virus in urban area. • Urban dengue outbreak is not associated with annual rainfall in Guangzhou. • Spatiotemporal satellite image fusion can investigate urban environmental change. • Urban environmental change could induce virus, vector, and dengue epidemic change.

  9. Potential effects of groundwater and surface water contamination in an urban area, Qus City, Upper Egypt

    Science.gov (United States)

    Abdalla, Fathy; Khalil, Ramadan

    2018-05-01

    The potential effects of anthropogenic activities, in particular, unsafe sewage disposal practices, on shallow groundwater in an unconfined aquifer and on surface water were evaluated within an urban area by the use of hydrogeological, hydrochemical, and bacteriological analyses. Physicochemical and bacteriological data was obtained from forty-five sampling points based on33 groundwater samples from variable depths and 12 surface water samples. The pollution sources are related to raw sewage and wastewater discharges, agricultural runoff, and wastewater from the nearby Paper Factory. Out of the 33 groundwater samples studied, 17 had significant concentrations of NO3-, Cl- and SO42-, and high bacteria counts. Most of the water samples from the wells contained high Fe, Mn, Pb, Zn, Cd, and Cr. The majority of surface water samples presented high NO3- concentrations and high bacteria counts. A scatter plot of HCO3- versus Ca indicates that 58% of the surface water samples fall within the extreme contamination zone, while the others are within the mixing zone; whereas 94% of groundwater samples showed evidence of mixing between groundwater and wastewater. The bacteriological assessment showed that all measured surface and groundwater samples contained Escherichia coli and total coliform bacteria. A risk map delineated four classes of contamination, namely, those sampling points with high (39.3%), moderate (36.3%), low (13.3%), and very low (11.1%) levels of contamination. Most of the highest pollution points were in the middle part of the urban area, which suffers from unmanaged sewage and industrial effluents. Overall, the results demonstrate that surface and groundwater in Qus City are at high risk of contamination by wastewater since the water table is shallow and there is a lack of a formal sanitation network infrastructure. The product risk map is a useful tool for prioritizing zones that require immediate mitigation and monitoring.

  10. Continued decrease of open surface water body area in Oklahoma during 1984-2015.

    Science.gov (United States)

    Zou, Zhenhua; Dong, Jinwei; Menarguez, Michael A; Xiao, Xiangming; Qin, Yuanwei; Doughty, Russell B; Hooker, Katherine V; David Hambright, K

    2017-10-01

    Oklahoma contains the largest number of manmade lakes and reservoirs in the United States. Despite the importance of these open surface water bodies to public water supply, agriculture, thermoelectric power, tourism and recreation, it is unclear how these water bodies have responded to climate change and anthropogenic water exploitation in past decades. In this study, we used all available Landsat 5 and 7 images (16,000 scenes) from 1984 through 2015 and a water index- and pixel-based approach to analyze the spatial-temporal variability of open surface water bodies and its relationship with climate and water exploitation. Specifically, the areas and numbers of four water body extents (the maximum, year-long, seasonal, and average extents) were analyzed to capture variations in water body area and number. Statistically significant downward trends were found in the maximum, year-long, and annual average water body areas from 1984 through 2015. Furthermore, these decreases were mainly attributed to the continued shrinking of large water bodies (>1km 2 ). There were also significant decreases in maximum and year-long water body numbers, which suggested that some of the water bodies were vanishing year by year. However, remarkable inter-annual variations of water body area and number were also found. Both water body area and number were positively related to precipitation, and negatively related to temperature. Surface water withdrawals mainly influenced the year-long water bodies. The smaller water bodies have a higher risk of drying under a drier climate, which suggests that small water bodies are more vulnerable under climate-warming senarios. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Using of standard marine radar for determination of a water surface and an atmosphere near-surface layer parameters

    Science.gov (United States)

    Bogatov, Nikolay A.; Bakhanov, Victor V.; Ermoshkin, Aleksei V.; Kazakov, Vasily I.; Kemarskaya, Olga N.; Titov, Victor I.; Troitskaya, Yulia I.

    2014-10-01

    At present time radar methods of the seas and oceans diagnostics are actively developing. Using of the radar stations based on satellites and planes allows to receive information on a sea surface and a atmosphere near-surface layer with coverage of big water surface areas independently of day time. The developed methods of satellite radio images processing can be applied to marine radar stations. In Institute of Applied Physics RAS works on sea surface diagnostics systems development on the basis of standard marine radar are actively conducted. Despite smaller coverage of the territory in comparison with satellite data, marine radar have possibility to record spatially temporary radar images and to receive information on a surrounding situation quickly. This work deals with results of the researches which were conducted within the international expedition in the Atlantic Ocean in the autumn of 2012 on a route Rotterdam (Netherlands) - Ushuaya (Argentina) - Antarctica — Ushuaya. During this expedition a complex measurements of a sea surface, a atmosphere near-surface layer parameters and subsurface currents in the wide range of hydroweather conditions, including the storm were carried out. The system developed in IAP RAS on the basis of a marine radar ICOM MR-1200RII and the ADC (Analog Digital Converter) block for data recording on the personal computer was used. Display of a non-uniform near-surface current on sea surface radar images in storm conditions is shown. By means of the high-speed anemometer and meteorological station the measurements of the atmosphere parameters were carried out. Comparison of the anemometer data with calculated from radar images is carried out. Dependence of radar cross section from wind speed in the wide range of wind speeds, including storm conditions is investigated. Possibility of marine radar using for surface waves intensity and ice situation estimates also as icebergs detection is shown.

  12. Endothelialization of artificial surfaces: does surface tension determine in vitro growth of human saphenous vein endothelial cells?

    Science.gov (United States)

    Fasol, R; Zilla, P; Deutsch, M; Fischlein, T; Kadletz, M; Griesmacher, A; Müller, M M

    1987-06-01

    To evaluate the possibility of providing, in vitro, an endothelial lining for artificial hearts, we cultivated adult autologous endothelial cells on two polyurethane and two silicone rubber surfaces. Over the ensuing 11-day period, we investigated the resulting cell proliferation and morphology by means of scanning electron and light microscopy. On the silicone rubber surfaces, seeding of 200,000 human saphenous vein endothelial cells per cm(2) produced an ideal cobblestone monolayer within a single day. In contrast, the polyurethane surfaces displayed an uneven, patchy distribution of endothelial cells. Scanning electron microscopy revealed microvilli and marginal overlapping in both groups. After the first day, the cell count on the polyurethane surfaces increased, whereas the count on the silicone rubber surfaces decreased. Morphologic investigations revealed that the ideally shaped cells initially on the silicone rubber had begun to overspread and subsequently to become detached, leaving denuded spheroid areas. Moreover, cultivation for 11 days on the polyurethane surfaces resulted in an unevenness of cell distribution that far exceeded the unevenness seen on the first day. Thus, despite the fact that materials with a high surface tension (such as silicone rubbers) seem to be ideal for initial cell spreading, subsequent cultivation results in cell detachment and death. On materials with a lower surface tension (such as polyurethanes), the less differentiated monolayers do at least proliferate, although their morphology remains unsatisfactory. Even if adult human endothelial cells should prove shear-stress-resistant, a minimum of 6 to 8 weeks would be required to establish autologous endothelial cell monolayers on the inner surface. Therefore, the endothelialization of artificial hearts is not possible when such hearts are used for urgent "bridging" before cardiac transplantation.

  13. Root surface areas of maxillary permanent teeth in anterior normal overbite and anterior open bite assessed using cone-beam computed tomography.

    Science.gov (United States)

    Suteerapongpun, Piyadanai; Sirabanchongkran, Supassara; Wattanachai, Tanapan; Sriwilas, Patiyut; Jotikasthira, Dhirawat

    2017-12-01

    The aim of this study was to compare the root surface areas of the maxillary permanent teeth in Thai patients exhibiting anterior normal overbite and in those exhibiting anterior open bite, using cone-beam computed tomography (CBCT). CBCT images of maxillary permanent teeth from 15 patients with anterior normal overbite and 18 patients with anterior open bite were selected. Three-dimensional tooth models were constructed using Mimics Research version 17.0. The cementoenamel junction was marked manually. The root surface area was calculated automatically by 3-Matic Research version 9.0. The root surface areas of each tooth type from both types of bite were compared using the independent t-test ( P <.05). The intraclass correlation coefficient was used to assess intraobserver reliability. The mean root surface areas of the maxillary central and lateral incisors in individuals with anterior open bite were significantly less than those in those with normal bite. The mean root surface area of the maxillary second premolar in individuals with anterior open bite was significantly greater than in those with normal bite. Anterior open-bite malocclusion might affect the root surface area, so orthodontic force magnitudes should be carefully determined.

  14. Determination of Optimum Viewing Angles for the Angular Normalization of Land Surface Temperature over Vegetated Surface

    Directory of Open Access Journals (Sweden)

    Huazhong Ren

    2015-03-01

    Full Text Available Multi-angular observation of land surface thermal radiation is considered to be a promising method of performing the angular normalization of land surface temperature (LST retrieved from remote sensing data. This paper focuses on an investigation of the minimum requirements of viewing angles to perform such normalizations on LST. The normally kernel-driven bi-directional reflectance distribution function (BRDF is first extended to the thermal infrared (TIR domain as TIR-BRDF model, and its uncertainty is shown to be less than 0.3 K when used to fit the hemispheric directional thermal radiation. A local optimum three-angle combination is found and verified using the TIR-BRDF model based on two patterns: the single-point pattern and the linear-array pattern. The TIR-BRDF is applied to an airborne multi-angular dataset to retrieve LST at nadir (Te-nadir from different viewing directions, and the results show that this model can obtain reliable Te-nadir from 3 to 4 directional observations with large angle intervals, thus corresponding to large temperature angular variations. The Te-nadir is generally larger than temperature of the slant direction, with a difference of approximately 0.5~2.0 K for vegetated pixels and up to several Kelvins for non-vegetated pixels. The findings of this paper will facilitate the future development of multi-angular thermal infrared sensors.

  15. Determination of depositional beryllium-10 fluxes in the area of the Laptev sea

    International Nuclear Information System (INIS)

    Strobl, C.; Schulz, V.; Schaeper, S.; Molnar, M.; Baumann, S.; Mangini; Kubik, P.W.

    1997-01-01

    A huge amount of continental 10 Be is delivered to the Arctic Ocean through the rivers. Our investigations show that the most extensive part of it is deposited directly in the shelf areas. The determined sedimentation flux densities in the continental slope and in the Central Arctic Ocean are in the range of the assumed atmospheric input of 10 Be and therefore clearly lower than in the shelf areas. (author) 1 fig., 2 refs

  16. Application of source-receptor models to determine source areas of biological components (pollen and butterflies)

    OpenAIRE

    M. Alarcón; M. Àvila; J. Belmonte; C. Stefanescu; R. Izquierdo

    2010-01-01

    The source-receptor models allow the establishment of relationships between a receptor point (sampling point) and the probable source areas (regions of emission) through the association of concentration values at the receptor point with the corresponding atmospheric back-trajectories, and, together with other techniques, to interpret transport phenomena on a synoptic scale. These models are generally used in air pollution studies to determine the areas of origin of chemical compounds measured...

  17. Determination of depositional beryllium-10 fluxes in the area of the Laptev sea

    Energy Technology Data Exchange (ETDEWEB)

    Strobl, C.; Schulz, V.; Schaeper, S.; Molnar, M.; Baumann, S.; Mangini [Heidelberger Akademie der Wissenschaften, Heidelberg (Germany); Kubik, P.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    A huge amount of continental {sup 10}Be is delivered to the Arctic Ocean through the rivers. Our investigations show that the most extensive part of it is deposited directly in the shelf areas. The determined sedimentation flux densities in the continental slope and in the Central Arctic Ocean are in the range of the assumed atmospheric input of {sup 10}Be and therefore clearly lower than in the shelf areas. (author) 1 fig., 2 refs.

  18. Soil Iodine Determination in Deccan Syneclise, India: Implications for Near Surface Geochemical Hydrocarbon Prospecting

    International Nuclear Information System (INIS)

    Mani, Devleena; Kumar, T. Satish; Rasheed, M. A.; Patil, D. J.; Dayal, A. M.; Rao, T. Gnaneshwar; Balaram, V.

    2011-01-01

    The association of iodine with organic matter in sedimentary basins is well documented. High iodine concentration in soils overlying oil and gas fields and areas with hydrocarbon microseepage has been observed and used as a geochemical exploratory tool for hydrocarbons in a few studies. In this study, we measure iodine concentration in soil samples collected from parts of Deccan Syneclise in the west central India to investigate its potential application as a geochemical indicator for hydrocarbons. The Deccan Syneclise consists of rifted depositional sites with Gondwana–Mesozoic sediments up to 3.5 km concealed under the Deccan Traps and is considered prospective for hydrocarbons. The concentration of iodine in soil samples is determined using ICP-MS and the values range between 1.1 and 19.3 ppm. High iodine values are characteristic of the northern part of the sampled region. The total organic carbon (TOC) content of the soil samples range between 0.1 and 1.3%. The TOC correlates poorly with the soil iodine (r 2 < 1), indicating a lack of association of iodine with the surficial organic matter and the possibility of interaction between the seeping hydrocarbons and soil iodine. Further, the distribution pattern of iodine compares well with two surface geochemical indicators: the adsorbed light gaseous hydrocarbons (methane through butane) and the propane-oxidizing bacterial populations in the soil. The integration of geochemical observations show the occurrence of elevated values in the northern part of the study area, which is also coincident with the presence of exposed dyke swarms that probably serve as conduits for hydrocarbon microseepage. The corroboration of iodine with existing geological, geophysical, and geochemical data suggests its efficacy as one of the potential tool in surface geochemical exploration of hydrocarbons. Our study supports Deccan Syneclise to be promising in terms of its hydrocarbon prospects.

  19. Hydrological and hydraulic models for determination of flood-prone and flood inundation areas

    Directory of Open Access Journals (Sweden)

    H. Aksoy

    2016-05-01

    Full Text Available Geographic Information Systems (GIS are widely used in most studies on water resources. Especially, when the topography and geomorphology of study area are considered, GIS can ease the work load. Detailed data should be used in this kind of studies. Because of, either the complication of the models or the requirement of highly detailed data, model outputs can be obtained fast only with a good optimization. The aim in this study, firstly, is to determine flood-prone areas in a watershed by using a hydrological model considering two wetness indexes; the topographical wetness index, and the SAGA (System for Automated Geoscientific Analyses wetness index. The wetness indexes were obtained in the Quantum GIS (QGIS software by using the Digital Elevation Model of the study area. Flood-prone areas are determined by considering the wetness index maps of the watershed. As the second stage of this study, a hydraulic model, HEC-RAS, was executed to determine flood inundation areas under different return period-flood events. River network cross-sections required for this study were derived from highly detailed digital elevation models by QGIS. Also river hydraulic parameters were used in the hydraulic model. Modelling technology used in this study is made of freely available open source softwares. Based on case studies performed on watersheds in Turkey, it is concluded that results of such studies can be used for taking precaution measures against life and monetary losses due to floods in urban areas particularly.

  20. Decadal changes of surface elevation over permafrost area estimated using reflected GPS signals

    Science.gov (United States)

    Liu, Lin; Larson, Kristine M.

    2018-02-01

    Conventional benchmark-based survey and Global Positioning System (GPS) have been used to measure surface elevation changes over permafrost areas, usually once or a few times a year. Here we use reflected GPS signals to measure temporal changes of ground surface elevation due to dynamics of the active layer and near-surface permafrost. Applying the GPS interferometric reflectometry technique to the multipath signal-to-noise ratio data collected by a continuously operating GPS receiver mounted deep in permafrost in Barrow, Alaska, we can retrieve the vertical distance between the antenna and reflecting surface. Using this unique kind of observables, we obtain daily changes of surface elevation during July and August from 2004 to 2015. Our results show distinct temporal variations at three timescales: regular thaw settlement within each summer, strong interannual variability that is characterized by a sub-decadal subsidence trend followed by a brief uplift trend, and a secular subsidence trend of 0.26 ± 0.02 cm year-1 during 2004 and 2015. This method provides a new way to fully utilize data from continuously operating GPS sites in cold regions for studying dynamics of the frozen ground consistently and sustainably over a long time.

  1. Cryptic oxygen oases: Hypolithic photosynthesis in hydrothermal areas and implications for Archean surface oxidation

    Science.gov (United States)

    Havig, J. R.; Hamilton, T. L.

    2017-12-01

    Mounting geochemical evidence suggests microorganisms capable of oxygenic photosynthesis (e.g., Cyanobacteria) colonized Archean continental surfaces, driving oxidative weathering of detrital pyrites prior to the 2.5 Ga great oxidation event. Modern terrestrial environments dominated by single-celled phototrophs include hydrothermal systems (e.g., Yellowstone National Park) and hypolithic communities found in arid to hyper-arid deserts (e.g., McMurdo Dry Valleys of Antarctica, Atacama Desert of Chile). Recent work indicates terrestrial hydrothermal systems date back at least as far as 3.5 Ga. Here, we explore phototrophic communities in both hypolithic (sub-sinter) and hydrothermal (subaqueous and subaerial) environments in Yellowstone National Park as potential analogs to Archean continental surfaces. Hydrothermal sub-sinter environments provide ideal conditions for phototrophic microbial communities, including blocking of harmful UV radiation, trapping and retention of moisture, and protection from erosion by rain and surface runoff. Hypolithic communities in geothermal settings were similar in both composition and carbon uptake rates to nearby hot spring communities. We hypothesize that hydrothermal area hypolithic communities represent modern analogs of phototrophic microbial communities that colonized Archean continental surfaces, producing oxygen locally and facilitating microbially-mediated pyrite oxidation prior to the presence of free oxygen in the global atmosphere. These results have implications for oxidation of the early Earth surface, the search for biosignatures in the rock record, as well as for potential harbors of past life on Mars and the search for life on Exoplanets.

  2. Correlation between surface reconstruction and polytypism in InAs nanowire selective area epitaxy

    Science.gov (United States)

    Liu, Ziyang; Merckling, Clement; Rooyackers, Rita; Richard, Olivier; Bender, Hugo; Mols, Yves; Vila, María; Rubio-Zuazo, Juan; Castro, Germán R.; Collaert, Nadine; Thean, Aaron; Vandervorst, Wilfried; Heyns, Marc

    2017-12-01

    The mechanism of widely observed intermixing of wurtzite and zinc-blende crystal structures in InAs nanowire (NW) grown by selective area epitaxy (SAE) is studied. We demonstrate that the crystal structure in InAs NW grown by SAE can be controlled using basic growth parameters, and wurtzitelike InAs NWs are achieved. We link the polytypic InAs NWs SAE to the reconstruction of the growth front (111)B surface. Surface reconstruction study of InAs (111) substrate and the following homoepitaxy experiment suggest that (111) planar defect nucleation is related to the (1 × 1) reconstruction of InAs (111)B surface. In order to reveal it more clearly, a model is presented to correlate growth temperature and arsenic partial pressure with InAs NW crystal structure. This model considers the transition between (1 × 1) and (2 × 2) surface reconstructions in the frame of adatom atoms adsorption/desorption, and the polytypism is thus linked to reconstruction quantitatively. The experimental data fit well with the model, which highly suggests that surface reconstruction plays an important role in the polytypism phenomenon in InAs NWs SAE.

  3. Assessment of Radioactive Materials and Heavy Metals in the Surface Soil around the Bayanwula Prospective Uranium Mining Area in China.

    Science.gov (United States)

    Bai, Haribala; Hu, Bitao; Wang, Chengguo; Bao, Shanhu; Sai, Gerilemandahu; Xu, Xiao; Zhang, Shuai; Li, Yuhong

    2017-03-14

    The present work is the first systematic and large scale study on radioactive materials and heavy metals in surface soil around the Bayanwula prospective uranium mining area in China. In this work, both natural and anthropogenic radionuclides and heavy metals in 48 surface soil samples were analyzed using High Purity Germanium (HPGe) γ spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS). The obtained mean activity concentrations of 238 U, 226 Ra, 232 Th, 40 K, and 137 Cs were 25.81 ± 9.58, 24.85 ± 2.77, 29.40 ± 3.14, 923.0 ± 47.2, and 5.64 ± 4.56 Bq/kg, respectively. The estimated average absorbed dose rate and annual effective dose rate were 76.7 ± 3.1 nGy/h and 83.1 ± 3.8 μ Sv, respectively. The radium equivalent activity, external hazard index, and internal hazard index were also calculated, and their mean values were within the acceptable limits. The estimated lifetime cancer risk was 3.2 × 10 -4 /Sv. The heavy metal contents of Cr, Ni, Cu, Zn, As, Cd, and Pb from the surface soil samples were measured and their health risks were then assessed. The concentrations of all heavy metals were much lower than the average backgrounds in China except for lead which was about three times higher than that of China's mean. The non-cancer and cancer risks from the heavy metals were estimated, which are all within the acceptable ranges. In addition, the correlations between the radionuclides and the heavy metals in surface soil samples were determined by the Pearson linear coefficient. Strong positive correlations between radionuclides and the heavy metals at the 0.01 significance level were found. In conclusion, the contents of radionuclides and heavy metals in surface soil around the Bayanwula prospective uranium mining area are at a normal level.

  4. The Use of an Infrared Thermometer to Determine Surface Temperatures in Marine Macroalgae

    Science.gov (United States)

    Olson, T. K.; Van Alstyne, K.

    2013-12-01

    The surface temperatures of intertidal algae may span a wide range at low tide, and there is a need for a quick yet accurate method to measure them. Infrared thermometers are used for measuring the temperatures of a variety of surfaces but, to our knowledge, have not been used to measure surface temperatures of marine macroalgae. These thermometers produce estimates of surface temperatures based upon measurements of infrared radiation and the emissivity of the surface being measured. In order to determine if this instrument would be suitable for measurements of macroalgal surface temperatures, variation in the emissivities of macroalgal surfaces had to first be determined. Emmisivities generally ranged from 0.93 to 0.98 and, with the exception of Chondrocanthus exasperatus, showed little variation among algal species, with the condition of the algal surface, or with layering. The differences in emissivities between C. exasperathus and other algal species might have been due to its papillate surface texture. Using an emissivity of 0.95, the infrared thermometer was then used to obtain the surface temperatures of a variety of intertidal algae in the field. Ulva lactuca and Porphyra sp. displayed the largest range of surface temperatures, while Ulvaria obscura and Mazzaella splendens varied the least.

  5. Determination of surface roughness and topography of dental resin-based nanocomposites using AFM analysis

    Directory of Open Access Journals (Sweden)

    Tijana Lainović

    2013-02-01

    Full Text Available The aim of this study was to determine surface roughness and topography of polished dental resin-based nanocomposites.Four representative dental resin-based nanocomposites were tested in the study: two nanohybrids (Filtek Z550 and Tetric EvoCeram and two nanofilled (Filtek Ultimate Body and Filtek Ultimate Translucent; and two reference materials: one microfilled (Gradia Direct and one microhybrid (Filtek Z250. Polymerized cylindrical specimens (4 mm x 2 mm were polished with multi-step polishing system-Super Snap. Immediately after the polishing, topography of each specimen was examined by Veeco di CP-II Atomic Force Microscope. Specimen’s surface has been scanned in 6 points in contact mode with CONT20A-CP tips. 1 Hz scan rate and 256 x 256 resolution were used to obtain topography on a 90 μm x 90 μm scanning area. Measured topography data were processed by Image Processing and Data Analysis V2.1.15 software. Following parameters were compared among specimens: average roughness and maximum peak-to-valley distance.All of the tested materials had similar average surface roughness after finishing and polishing procedure. The lowest values occurred in the material Filtek Ultimate Body, and the highest in the Filtek Z550. When interpreting maximum peak-to-valley distance the larger differences in values (up to 100% occurred in Filtek Z550, Filtek Z250 and Filtek Ultimate Body, which is a result of the deep polishing channels and tracks. Type, size, distribution of fillers and filler loading in tested materials, didn’t influence average roughness values, but had an impact on maximum peak-to-valley distance values.

  6. Clay Mineralogy Studies of Soils Located on Different Geomorphic Surfaces in Jabalbarez-Jiroft Area

    Directory of Open Access Journals (Sweden)

    naser boroumand

    2017-02-01

    Full Text Available Introduction: Soil and geomorphology are closely related to each other. That is why considering geomorphic concepts in soil genesis and classification studies may cause a better understanding of soil genesis processes. Paleosols with argillic horizons were investigated on stable pediment surfaces in Jiroft area, central Iran, by Sanjari et al. (2011. They found that secondary gypsum and calcium carbonate were accumulated in mantled pediments, but moving down the slope toward lowlands, salts more soluble than gypsum have been accumulated. Clay mineralogy in soil researches helps to better studying soil genesis and development. A quantitative and qualitative study of clay minerals together with their structural composition provides valuable data on the absorption, fixation, and desorption of different cations in soils. Smectite, chlorite, illite, vermiculite, kaolinite, palygorskite, and sepiolite were reported as dominant clay minerals found in arid and semi-arid areas. The objectives of the present study are to evaluate the clay mineralogy of Jabalbarez-Jiroft soils on different geomorphic surfaces. Materials and Methods: The study area was located in Jabalbarez, 200 Km south Kerman, Central Iran. Fig. 1 showed the exact location of study area. Soil temperature and moisture regimes of the area were thermic and aridic, respectively. Hill, rock pediment, mantled pediment and piedmont alluvial plain landforms were identified, using aerial photo interpretation, topography and geological map observation, in addition to detailed field works. Air-dried soil samples were crushed and passed through a 2-mm sieve. Routine physicochemical analyses wereperformed on the samples. Undisturbed soil samples from the Bt horizon of pedons 4, 5 and 6 were chosen for micromorphology investigations. Beside, eight samples including A and C2 horizons of pedon 1, A and Bt horizon of pedon 3, Bt and Bw horizons of pedon 4, and Bt and C horizon of pedon 5 were selected for

  7. Quantifying watershed surface depression storage: determination and application in a hydrologic model

    Science.gov (United States)

    Joseph K. O. Amoah; Devendra M. Amatya; Soronnadi. Nnaji

    2012-01-01

    Hydrologic models often require correct estimates of surface macro-depressional storage to accurately simulate rainfall–runoff processes. Traditionally, depression storage is determined through model calibration or lumped with soil storage components or on an ad hoc basis. This paper investigates a holistic approach for estimating surface depressional storage capacity...

  8. Determination of optimum "multi-channel surface wave method" field parameters.

    Science.gov (United States)

    2012-12-01

    Multi-channel surface wave methods (especially the multi-channel analyses of surface wave method; MASW) are routinely used to : determine the shear-wave velocity of the subsurface to depths of 100 feet for site classification purposes. Users are awar...

  9. Estimation of small reservoir storage capacities in the São Francisco, Limpopo, Bandama and Volta river basins using remotely sensed surface areas

    Science.gov (United States)

    Rodrigues, Lineu; Senzanje, Aidan; Cecchi, Philippe; Liebe, Jens

    2010-05-01

    area, depth and shape. Depth was measured using a stadia rod or a manual echosounder. For reservoirs in the sub-set, estimated surface area was used as an input into the triangulated irregular network model. With the surface area and depth, measured volume was calculated. Comparisons were made between estimates of surface area from field surveys and estimates of surface area from remote sensing. A linear regression analysis was carried out to establish the relationship between surface area and storage capacities. Within geomorphologically homogenous regions, one may expect a good correlation between the surface area, which may be determined through satellite observations, and the stored volume. Such a relation depends on the general shape of the slopes (convex, through straight, to concave). The power relationships between remotely sensed surface areas (m^2) and storage capacities of reservoirs (m^3) obtained were - Limpopo basin (Lower Mzingwane sub-catchment): Volume = 0.023083 x Area^1.3272 (R2 = 95%); Bandama basin (North of the basin in Ivory Coast): Volume = 0.00405 x Area^1.4953 (R2 = 88.9%); Volta basin (Upper East region of the Volta Basin in Ghana): Volume = 0.00857 × Area^1.43 (R2 = 97.5%); São Francisco basin (Preto river sub-catchment): Volume = 0.2643 x Area^1.1632 (R2 = 92.1%). Remote sensing was found to be a suitable means to detect small reservoirs and accurately measure their surface areas. The general relationship between measured reservoir volumes and their remotely sensed surface areas showed good accuracy for all four basins. Combining such relationships with periodical satellite-based reservoir area measurements may allow hydrologists and planners to have clear picture of water resource system in the Basins, especially in ungauged sub-basins.

  10. Mathematical model for biomolecular quantification using large-area surface-enhanced Raman spectroscopy mapping

    DEFF Research Database (Denmark)

    Palla, Mirkó; Bosco, Filippo; Yang, Jaeyoung

    2015-01-01

    Surface-enhanced Raman spectroscopy (SERS) based on nanostructured platforms is a promising technique for quantitative and highly sensitive detection of biomolecules in the field of analytical biochemistry. Here, we report a mathematical model to predict experimental SERS signal (or hotspot......) intensity distributions of target molecules on receptor-functionalized nanopillar substrates for biomolecular quantification. We demonstrate that by utilizing only a small set of empirically determined parameters, our general theoretical framework agrees with the experimental data particularly well...

  11. Applicability of the Guggenheim–Anderson–Boer water vapour sorption model for estimation of soil specific surface area

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Tuller, Markus; Møldrup, Per

    2018-01-01

    Soil specific surface area (SA) controls fundamental soil processes such as retention of water, ion exchange, and adsorption and release of plant nutrients and contaminants. Conventional methods for determining SA include adsorption of polar or non‐polar fluid molecules with associated advantages...... parameters varied depending on the water activity or relative humidity range of measured data (0.03–0.93 compared with 0.10–0.80), whereas the variation for desorption was minimal. For desorption isotherms, the average water activity value at which the GAB monolayer parameter was obtained was 0......‐based modelling approaches to determine SA. Measured water vapour adsorption and desorption isotherms for 321 soil samples were used to parameterize the GAB model, the Brunauer–Emmet–Teller (BET) equation and a film adsorption Tuller–Or (TO) model to estimate SA. For adsorption isotherms, the values of the GAB...

  12. Determination of natural radioactivity of groundwater and surface of Brumadinho and Nova Lima, Brazil

    International Nuclear Information System (INIS)

    Faria, Ligia Santana de

    2013-01-01

    The municipalities of Brumadinho and Nova Lima are located in the metropolitan area of Belo Horizonte city. They are of ecological interest since they belong to an Environmental Protection Area, which is located on a very important deposit of iron ore. In addition of mineral wealth, the region has a geological characteristic that includes quartzitic conglomerates associated with uranium and significant potential underground water with hydrogeological characteristics very particular and complex, as the Quartzite Aquifer, which belongs to a geological formation called the 'Moeda Formation'. In the present work radiometric measurements were performed for 44 water samples. The samples were collected in four geographical points, three of them situated in Brumadinho (surface water) and one point situated in Nova Lima municipality (underground water). The period of sampling extended for a thirteen months period. Some of these locations was used as an alternative sampling point. Uranium and thorium concentrations of the samples were determined using an Inductively Coupled Plasma Mass Spectrometer. The content of gross alpha and gross beta activity, and the concentration of the radionuclides 226 Ra, 228 Ra e 210 Pb were determinate by using Spectrometer Liquid Scintillation. In this case was necessary to calibrate the spectrometer using 241 Am e 90 Sr/ 90 Y standards. The resultants values were compared with those recommended by the World Health Organization, Ministry of Health and the National Council of the Environment. The maximum level of water natural radioactivity found was 0,275 ± 0,052 Bq.L -1 for gross alpha radiation, 0,130 ± 0,046 Bq.L -1 for 226 Ra and 0,096 ± 0,005 Bq.L-1 for 228 Ra. The levels of gross beta activity and 210 Pb were below the detection limit. The maximum concentrations of uranium and thorium found were 0,068 μg.L -1 and 0.027 μg.L -1 respectively. (author)

  13. Influence of Alkali Treatment on the Surface Area of Aluminium Dross

    Directory of Open Access Journals (Sweden)

    N. S. Ahmad Zauzi

    2016-01-01

    Full Text Available Aluminium dross is an industrial waste from aluminium refining industry and classified as toxic substances. However, the disposal of dross as a waste is a burden to aluminium manufacturer industries due to its negative effects to the ecosystem, surface, and ground water. Therefore the purpose of this study is to evaluate the influence of sodium hydroxide (NaOH on the surface area and pore size of aluminium dross. There were 3 stages in the treatment activities, which were leaching, precipitation, and calcination process. The optimum result from this study was the surface area of aluminium dross increases from 10.1 m2/g up to 80.0 m2/g at 40°C, 1% NaOH, and 15-minute reaction time. Thus, aluminium dross has a potential to be converted into other useful material such as catalyst and absorbent. The benefit of this research is that the hazardous industrial waste can be turned into wealth to be used in other applications such as in catalytic activities and absorber in waste water treatment. Further investigation on the physicochemical of aluminium dross with different acid or alkali should be conducted to get deeper understanding on the aluminium dross as a catalyst-type material.

  14. Water content determination of soil surface in an intensive apple orchard

    Science.gov (United States)

    Riczu, Péter; Nagy, Gábor; Tamás, János

    2015-04-01

    Currently in Hungary, less than 100,000 hectares of orchards can be found, from which cultivation of apple is one of the most dominant ones. Production of marketable horticulture products can be difficult without employing advanced and high quality horticulture practices, which, in turn, depends on appropriate management and irrigation systems, basically. The got out water amount depend on climatic, edafic factors and the water demand of plants as well. The soil water content can be determined by traditional and modern methods. In order to define soil moisture content, gravimetry measurement is one of the most accurate methods, but it is time consuming and sometimes soil sampling and given results are in different times. Today, IT provides the farmers such tools, like global positioning system (GPS), geographic information system (GIS) and remote sensing (RS). These tools develop in a great integration rapidly. RS methods are ideal to survey larger area quick and accurate. Laser scanning is a novel technique which analyses a real-world or object environment to collect structural and spectral data. In order to obtain soil moisture information, the Leica ScanStation C10 terrestrial 3D laser scanner was used on an intensive apple orchard on the Study and Regional Research Farm of the University of Debrecen, near Pallag. Previously, soil samples from the study area with different moisture content were used as reference points. Based on the return intensity values of the laser scanner can be distinguished the different moisture content areas of soil surface. Nevertheless, the error of laser distance echo were examined and statistically evaluated. This research was realized in the frames of TÁMOP 4.2.4. A/2-11-1-2012-0001 "National Excellence Program - Elaborating and operating an inland student and researcher personal support system". The project was subsidized by the European Union and co-financed by the European Social Fund.

  15. Determinants of Non-Home-Prepared Food Consumption in Two Low-Income Areas in Nairobi

    NARCIS (Netherlands)

    Riet, van 't H.; Hartog, den A.P.; Hooftman, D.A.P.; Foeken, D.W.J.; Mwangi, A.M.; Staveren, van W.A.

    2003-01-01

    OBJECTIVE: Street foods are an important source of nutrients for poor urban residents. This study aimed to identify determinants of the proportion of daily energy provided by non-home-prepared foods. METHODS: A survey was conducted in a slum and a low- to middle-income area of Nairobi. The survey

  16. Determination of representative elementary areas for soil redoximorphic features by digital image processing

    Science.gov (United States)

    Photography has been a welcome tool in documenting and conveying qualitative soil information. When coupled with image analysis software, the usefulness of digital cameras can be increased to advance the field of micropedology. The determination of a Representative Elementary Area (REA) still rema...

  17. Characteristics of surface O{sub 3} over Qinghai Lake area in Northeast Tibetan Plateau, China

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Zhenxing, E-mail: zxshen@mail.xjtu.edu.cn [Department of Environmental Sciences and Engineering, Xi' an Jiaotong University, Xi' an (China); Key Lab of Aerosol, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an (China); Cao, Junji [Key Lab of Aerosol, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an (China); Zhang, Leiming [Air Quality Research Division, Environment Canada, Toronto (Canada); Zhao, Zhuzi [Key Lab of Aerosol, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an (China); Dong, Jungang [School of Architecture, Xi' an University of Architecture and Technology, Xi' an 710055 (China); Wang, Linqing [Department of Environmental Sciences and Engineering, Xi' an Jiaotong University, Xi' an (China); Wang, Qiyuan; Li, Guohui; Liu, Suixin [Key Lab of Aerosol, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi' an (China); Zhang, Qian [Department of Environmental Sciences and Engineering, Xi' an Jiaotong University, Xi' an (China)

    2014-12-01

    Surface O{sub 3} was monitored continuously during Aug. 12, 2010 to Jul. 21, 2011 at a high elevation site (3200 m above sea level) in Qinghai Lake area (36°58′37″N, 99°53′56″E) in Northeast Tibetan Plateau, China. Daily average O{sub 3} ranged from 21.8 ppbv to 65.3 ppbv with an annual average of 41.0 ppbv. Seasonal average of O{sub 3} followed a decreasing order of summer > autumn > spring > winter. Diurnal variations of O{sub 3} showed low concentrations during daytime and high concentrations during late night and early morning. An intensive campaign was also conducted during Aug. 13–31, 2010 to investigate correlations between meteorological or chemical conditions and O{sub 3}. It was found that O{sub 3} was poorly correlated with solar radiation due to the insufficient NO{sub x} in the ambient air, thus limiting O{sub 3} formation under strong solar radiation. In contrast, high O{sub 3} levels always coincided with strong winds, suggesting that stratospheric O{sub 3} and long range transport might be the main sources of O{sub 3} in this rural area. Back-trajectory analysis supported this hypothesis and further indicated the transport of air masses from northwest, northeast and southeast directions. - Highlights: • Surface O{sub 3} was measured in Qinghai Lake area in Northeast Tibetan Plateau, China. • The O{sub 3} chemical formation was under a strong NOx-limited in Qinghai Lake areas. • Stratospheric O{sub 3} and transport might be the main sources of O{sub 3} in this area.

  18. Characteristics of surface O3 over Qinghai Lake area in Northeast Tibetan Plateau, China

    International Nuclear Information System (INIS)

    Shen, Zhenxing; Cao, Junji; Zhang, Leiming; Zhao, Zhuzi; Dong, Jungang; Wang, Linqing; Wang, Qiyuan; Li, Guohui; Liu, Suixin; Zhang, Qian

    2014-01-01

    Surface O 3 was monitored continuously during Aug. 12, 2010 to Jul. 21, 2011 at a high elevation site (3200 m above sea level) in Qinghai Lake area (36°58′37″N, 99°53′56″E) in Northeast Tibetan Plateau, China. Daily average O 3 ranged from 21.8 ppbv to 65.3 ppbv with an annual average of 41.0 ppbv. Seasonal average of O 3 followed a decreasing order of summer > autumn > spring > winter. Diurnal variations of O 3 showed low concentrations during daytime and high concentrations during late night and early morning. An intensive campaign was also conducted during Aug. 13–31, 2010 to investigate correlations between meteorological or chemical conditions and O 3 . It was found that O 3 was poorly correlated with solar radiation due to the insufficient NO x in the ambient air, thus limiting O 3 formation under strong solar radiation. In contrast, high O 3 levels always coincided with strong winds, suggesting that stratospheric O 3 and long range transport might be the main sources of O 3 in this rural area. Back-trajectory analysis supported this hypothesis and further indicated the transport of air masses from northwest, northeast and southeast directions. - Highlights: • Surface O 3 was measured in Qinghai Lake area in Northeast Tibetan Plateau, China. • The O 3 chemical formation was under a strong NOx-limited in Qinghai Lake areas. • Stratospheric O 3 and transport might be the main sources of O 3 in this area

  19. Assessment of mercury erosion by surface water in Wanshan mercury mining area.

    Science.gov (United States)

    Dai, ZhiHui; Feng, Xinbin; Zhang, Chao; Shang, Lihai; Qiu, Guangle

    2013-08-01

    Soil erosion is a main cause of land degradation, and in its accelerated form is also one of the most serious ecological environmental problems. Moreover, there are few studies on migration of mercury (Hg) induced by soil erosion in seriously Hg-polluted districts. This paper selected Wanshan Hg mining area, SW China as the study area. Revised universal soil loss equation (RUSLE) and Geographic information system (GIS) methods were applied to calculate soil and Hg erosion and to classify soil erosion intensity. Our results show that the soil erosion rate can reach up to 600,884tkm(-2)yr(-1). Surfaces associated with very slight and extremely severe erosion include 76.6% of the entire land in Wanshan. Furthermore, the cumulative erosion rates in the area impacted by extremely severe erosion make up 90.5% of the total. On an annual basis, Hg surface erosion load was predicted to be 505kgyr(-1) and the corresponding mean migration flux of Hg was estimated to be 3.02kgkm(-2)yr(-1). The erosion loads of Hg resulting from farmland and meadow soil were 175 and 319kgyr(-1) respectively, which were enhanced compared to other landscape types due to the fact that they are generally located in the steep zones associated with significant reclamation. Contributing to establish a mass balance of Hg in Wanshan Hg mining area, this study supplies a dependable scientific basis for controlling soil and water erosion in the local ecosystems. Land use change is the most effective way for reducing Hg erosion load in Wanshan mining area. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Surface deformation of active volcanic areas retrieved with the SBAS-DInSAR technique: an overview

    Directory of Open Access Journals (Sweden)

    G. Zeni

    2008-06-01

    Full Text Available This paper presents a comprehensive overview of the surface deformation retrieval capability of the Differential Synthetic Aperture Radar Interferometry (DInSAR algorithm, referred to as Small BAseline Subset (SBAS technique, in the context of active volcanic areas. In particular, after a brief description of the algorithm some experiments relevant to three selected case-study areas are presented. First, we concentrate on the application of the SBAS algorithm to a single-orbit scenario, thus considering a set of SAR data composed by images acquired on descending orbits by the European Remote Sensing (ERS radar sensors and relevant to the Long Valley caldera (eastern California area. Subsequently, we address the capability of the SBAS technique in a multipleorbit context by referring to Mt. Etna volcano (southern Italy test site, with respect to which two different ERS data set, composed by images acquired both on ascending and descending orbits, are available. Finally, we take advantage of the capability of the algorithm to work in a multi-platform scenario by jointly exploiting two different sets of SAR images collected by the ERS and the Environment Satellite (ENVISAT radar sensors in the Campi Flegrei caldera (southern Italy area. The presented results demonstrate the effectiveness of the algorithm to investigate the deformation field in active volcanic areas and the potential of the DInSAR methodologies within routine surveillance scenario.

  1. Visualization of Lake Mead Surface Area Changes from 1972 to 2009

    Directory of Open Access Journals (Sweden)

    David M. Atkinson

    2012-06-01

    Full Text Available For most of the last decade, the south-western portion of the United States has experienced a severe and enduring drought. This has caused serious concerns about water supply and management in the region. In this research, 30 orthorectified Landsat satellite images from the United States Geological Service (USGS Earth Explorer archive were analyzed for the 1972 to 2009 period. The images encompassed Lake Mead (a major reservoir in this region and were examined for changes in water surface area. Decadal lake area minimums/maximums were achieved in 1972/1979, 1981/1988, 1991/1998, and 2009/2000. The minimum lake area extent occurred in 2009 (356.4 km2, while the maximum occurred in 1998 (590.6 km2. Variable trends in water level and lake area were observed throughout the analysis period, however progressively lower values were observed since 2000. The Landsat derived lake areas show a very strong relationship with actual measured water levels at the Hoover Dam. Yearly water level variations at the dam vary minimally from the satellite derived estimates. A complete (yearly record of satellite images may have helped to reduce the slight deviations in the time series.

  2. Estimating Surface Area of Sponges and Marine Gorgonians as Indicators of Habitat Availability on Caribbean Coral Reefs

    Science.gov (United States)

    Surface area and topographical complexity are fundamental attributes of shallow tropical coral reefs and can be used to estimate habitat for fish and invertebrates. This study presents empirical methods for estimating surface area provided by sponges and gorgonians in the Central...

  3. Groundwater impact on surface water quality and nutrient loads in lowland polder catchments: monitoring the greater Amsterdam area

    NARCIS (Netherlands)

    Yu, L.; Rozemeijer, J.; Breukelen, B.M. van; Ouboter, M.; Vlugt, C. van der; Broers, H.P.

    2018-01-01

    The Amsterdam area, a highly manipulated delta area formed by polders and reclaimed lakes, struggles with high nutrient levels in its surface water system. The polders receive spatially and temporally variable amounts of water and nutrients via surface runoff, groundwater seepage, sewer leakage, and

  4. Groundwater impacts on surface water quality and nutrient loads in lowland polder catchments : Monitoring the greater Amsterdam area

    NARCIS (Netherlands)

    Yu, Liang; Rozemeijer, Joachim; van Breukelen, B.M.; Ouboter, Maarten; Van Der Vlugt, Corné; Broers, Hans Peter

    2018-01-01

    The Amsterdam area, a highly manipulated delta area formed by polders and reclaimed lakes, struggles with high nutrient levels in its surface water system. The polders receive spatially and temporally variable amounts of water and nutrients via surface runoff, groundwater seepage, sewer leakage,

  5. Atomic layer deposition of highly dispersed Pt nanoparticles on a high surface area electrode backbone for electrochemical promotion of catalysis

    NARCIS (Netherlands)

    Hajar, Y.; di Palma, V.; Kyriakou, V.; Verheijen, M. A.; Baranova, E. A.; Vernoux, P.; Kessels, W. M. M.; Creatore, M.; van de Sanden, M. C. M.; Tsampas, M. N.

    2017-01-01

    A novel catalyst design for electrochemical promotion of catalysis (EPOC) is proposed which overcomes the main bottlenecks that limit EPOC commercialization, i.e., the low dispersion and small surface area of metal catalysts. We have increased the surface area by using a porous composite electrode

  6. Characteristics of PAHs adsorbed on street dust and the correlation with specific surface area and TOC.

    Science.gov (United States)

    Wang, Chengkun; Li, Yingxia; Liu, Jingling; Xiang, Li; Shi, Jianghong; Yang, Zhifeng

    2010-10-01

    Street dust was collected from five roads with different traffic volumes in the metropolitan area of Beijing and separated into five size fractions. Concentrations of polycyclic aromatic hydrocarbons (PAHs) adsorbed on street dust in different size ranges and their correlation with specific surface area and total organic carbon (TOC) were investigated. Results show that the concentration of 16-PAHs of sieved samples ranges from 0.27 to 1.30 mg/kg for all the sampling sites. Particles smaller than 40 mum in diameter have the highest 16-PAHs concentration among all of the size ranges for street dust from the four sampling sites with vehicles running on. PAHs with three or four rings account for 68% of the overall 16-PAHs on average. Remarkable positive correlation exists between 16-PAHs concentration and specific surface area with R(2) values from 0.7 to 0.96 for the four sampling sites with vehicles running on. The relationship between the concentration of 16-PAHs and TOC is less clear.

  7. Monitoring of the Earth's surface deformation in the area of water dam Zarnowiec

    Science.gov (United States)

    Mojzes, Marcel; Wozniak, Marek; Habel, Branislav; Macak, Marek

    2017-04-01

    Mathematical and physical research directly motivates geodetic community which can provide very accurate measurements for testing of the proposed models Earth's surface motion near the water dams should be monitored due to the security of the area. This is a process which includes testing of existing models and their physical parameters. Change of the models can improve the practical results for analyzing the trends of motion in the area of upper reservoir of water dam Zarnowiec. Since 1998 Warsaw University of Technology realized a research focused on the horizontal displacements of the upper reservoir of water dam Zarnowiec. The 15 selected control points located on the upper reservoir crown of the water dam were monitored by classical distance measurements. It was found out that changes in the object's geometry occur due to the variation of the water level. The control measurements of the changes in the object's geometry occurring during the process of emptying and filling of the upper reservoir of water dam were compared with the deformations computed using improved Boussinesqués method programmed in the software MATLAB and ANSYS for elastic and isotropic half space as derivation of suitable potentials extended to the loaded region. The details and numerical results of this process are presented This presentation was prepared within the project "National Centre for Diagnostic of the Earth's Surface Deformations in the Area of Slovakia", ITMS code: 26220220108.

  8. A mathematical model for leak location and leak area determination in pipeline networks

    Directory of Open Access Journals (Sweden)

    Oyedokun O.I.

    2013-01-01

    Full Text Available Prompt leak location and leak area determination in oil and gas pipeline installations is an indispensable approach to controlling petroleum products wastages in pipes. However, there is an evident lack of literature information on this subject. In this paper, we modelled leak location detection and leak area determination in pipes by applying two methodologies and gave an illustrative example using simulated data with the aid of Matlab. A comparison of these two approaches resulted in an error of 6.24%, suggesting that the closer the leak is to the measurement station, the lower will be the time interval between two successive waves that will pass through the leak and get to the measurement station. The relationship between the pipe area and coefficient of reflection is parabolic. This contribution is valuable to pipeline engineers in the economic control of leaks.

  9. Overview on the Surface Functionalization Mechanism and Determination of Surface Functional Groups of Plasma Treated Carbon Nanotubes.

    Science.gov (United States)

    Saka, Cafer

    2018-01-02

    The use of carbon materials for many applications is due to the unique diversity of structures and properties ranging from chemical bonds between the carbon atoms of the materials to nanostructures, crystallite alignment, and microstructures. Carbon nanotubes and other nanoscale carbonaceous materials draw much attention due to their physical and chemical properties, such as high strength, high resistance to corrosion, electrical and thermal conductivity, stability and a qualified adsorbent. Carbon-based nanomaterials, which have a relatively large specific area and layered structure, can be used as an adsorbent for efficient removal of organic and inorganic contaminants. However, one of the biggest obstacles to the development of carbon-based nanomaterials adsorbents is insolubility and the lack of functional groups on the surface. There are several approaches to introduce functional groups on carbon nanotubes. One of these approaches, plasma applications, now has an important place in the creation of surface functional groups as a flexible, fast, and environmentally friendly method. This review focuses on recent information concerning the surface functionalization and modification of plasma treated carbon nanotube. This review considers the surface properties, advantages, and disadvantages of plasma-applied carbon nanotubes. It also examines the reaction mechanisms involved in the functional groups on the surface.

  10. The importance of the active surface area of graphite materials in the first lithium intercalation

    Energy Technology Data Exchange (ETDEWEB)

    Novak, P.; Ufheil, J.; Buqa, H. [Paul Scherrer Institut, Electrochemistry Laboratory, CH-5232 Villigen PSI (Switzerland); Krumeich, F. [ETH Zuerich, Laboratory of Inorganic Chemistry, CH-8093 Zurich (Switzerland); Spahr, M.E.; Goers, D.; Wilhelm, H.; Vix-Guterl, C. [TIMCAL SA, CH-6743 Bodio TI (Switzerland); Dentzer, J.; Gadiou, R. [Institut de Chimie des Surfaces et Interfaces, CNRS UPR 9069, F-68057 Mulhouse Cedex (France)

    2007-12-06

    When lithium is intercalated into graphite in ethylene carbonate (EC) containing electrolytes, solvent co-intercalation leading to the exfoliation of the graphite structure could occur. The exfoliation can be suppressed if an efficient solid electrolyte interphase (SEI, a passivation layer) is formed. Here we study the role played by the active surface area (ASA) of graphite materials during their first electrochemical reduction. ASA (related to the presence of defects at the carbon surface) appears as a critical graphite surface parameter influencing the surface passivation mechanism and the graphite exfoliation. The ASA of TIMREX {sup registered} SLX50 synthetic graphite was modified by thermal treatment in argon and air. The electrochemical performance was characterized in 1 M LiPF{sub 6}, EC:DMC electrolyte and post mortem analyses were performed by SEM imaging. It turned out that a decrease of the graphite ASA, i.e., an increase of the graphite structural order, hinders the formation of the passivation layer and favors the exfoliation process. In contrast, the exfoliation of the same graphite can be suppressed if its ASA is increased for example by air treatment. The ASA of the graphite kinetically controls the formation of an efficient SEI film and accordingly the irreversible charge loss is much lower in the case of graphite with a high ASA value. (author)

  11. Blasting injuries in surface mining with emphasis on flyrock and blast area security

    Energy Technology Data Exchange (ETDEWEB)

    Bajpayee, T.S.; Rehak, T.R.; Mowrey, G.L.; Ingram, D.K. [NIOSH, Pittsburgh, PA (USA). Pittsburgh Research Lab.

    2004-07-01

    Blasting is a hazardous component of surface mining. Serious injuries and fatalities result from improper judgment or practice during rock blasting. This paper describes several fatal injury case studies, analyzes causative factors, and emphasizes preventive measures. During the 21-year period from 1978 to 1998, the mean yearly explosive-related injuries (fatal and nonfatal) for surface coal mines was 8.86 (95% CI: 6.38-11.33), and for surface metal/nonmetal mines 10.76 (95% CI: 8.39-13.14). Flyrock and lack of blast area security accounted for 68.2% of these injuries. Case studies indicate that the causative factors for fatal injuries are primarily personal and task-related and to some extent environmental. A reduction in the annual injuries in surface coal mines was observed during the 10-year period of 1989-1998 (5.80 (95% CI: 2.71-8.89)) compared to the previous 10-year period of 1979-1988 (10.90 (95% CI: 7.77-14.14)). However, such reduction was not noticed in the metal/nometal sector (i.e., 9.30 (95% CI: 6.84-11.76) for the period 1989-1998 compared with 11.00 (95% CI: 7.11-14.89) for the period 1979-1988). Discussion of case studies during safety meetings will help to mitigate fatal injuries and derive important payoffs in terms of lower risks and costs of injuries.

  12. The determination of oxygen in molybdenum and tungsten monocrystals taking into account the surface oxygen contribution

    International Nuclear Information System (INIS)

    Aleksandrov, V.D.; Egiazarov, B.G.; Polyakova, I.S.; Sel'dyakov, Yu.P.; Chernyavskij, V.T.

    1977-01-01

    The method has been developed for determining oxygen content in molybdenum and tungsten usign the neutron activation analysis. The sensitivity is 1.6X10 -5 and 1.3x10 -3 wt.% for molybdenum and tungsten, respectively. The density of oxygen distribution in surface layers has been experimentally evaluated. It is shown that the oxygen presence in a surface layer of molybdenum and tungsten does not impede oxygen determination in the bulk of the sample, when the oxygen content is >5x10 -5 wt.%. If oxygen content is -3 wt.%, the presence of oxygen in the surface layer should be taken into account

  13. Dissolution Effects on Specific Surface Area, Particle Size, and Porosity of Pentelic Marble.

    Science.gov (United States)

    Orkoula, Malvina G.; Koutsoukos, Petros G.

    2001-07-15

    Dissolution of natural stone such as marble is not limited to its surface. The porous structure, known to play an important role in stone decay, is also affected by the conditions of dissolution. In the present work, the changes in pore size distribution of Pentelic marble particles accompanying chemical dissolution in undersaturated solutions and at alkaline pH 8.25 were investigated. The specific surface area and the mesopore distribution of the Pentelic marble tested showed a pronounced decrease to very low values. On the other hand, the sizes of macropores exhibited a tendency to increase with the extent of dissolution due either to dissolution in the interior of the pores or to fusion of small pores into larger. Furthermore, the number of small particles decreased significantly, reaching complete disappearance, depending on the extent of dissolution. At the same time, the relative number of particles of intermediate size increased. Copyright 2001 Academic Press.

  14. Ultrasonic determination of interfacial area, void fraction and Sauter mean diameter in bubbly flow

    International Nuclear Information System (INIS)

    Bensler, Henri-Paul

    1990-01-01

    In this research thesis, the author shows that it is possible to determine, by means of a single measurement, the interface surface, the vacuum rate, and the Sauter mean diameter in a bubbly water-air flow. The developed technique relies on the measurement of the attenuation of an ultrasound beam by the two-phase medium, and on the use of broadband transducers associated with a multi-frequency screening method. Tests in standing water or in forced convection are performed in ducts with a square cross section with a side of 40, 80, or 120 mm. Values obtained with ultrasounds are compared with those determined by using photographs (interface surfaces, Sauter diameters) or by using a gauge pressure, or by using X rays (vacuum rate). This method based on ultrasound attenuation reveals to be simple and in good agreement with reference methods [fr

  15. Sociocultural influences on the determinants of breast-feeding by Latina mothers in the Cincinnati area.

    Science.gov (United States)

    Vaughn, Lisa M; Ireton, Candace; Geraghty, Sheela R; Diers, Tiffiny; Niño, Vanessa; Falciglia, Grace A; Valenzuela, Jessica; Mosbaugh, Christine

    2010-01-01

    While breast-feeding initiation and duration among US Latina women appear to decrease with acculturation, health care providers in the Greater Cincinnati area have noted lower rates of breast-feeding among even first-generation Latina immigrants. This study's purpose was to identify determinants of breast-feeding for Latina mothers in Cincinnati through qualitative interviews and Spanish Breastfeeding Self-Efficacy Scale ratings. Our findings suggest that, along with similar levels of breast-feeding self-confidence, foreign-born Latina women in the Greater Cincinnati area share similar breast-feeding determinants with the general population. However, characteristics of these determinants and their impact vary because of unique pressures experienced by this community.

  16. Tuning Porosity and Surface Area in Mesoporous Silicon for Application in Li-Ion Battery Electrodes.

    Science.gov (United States)

    Cook, John B; Kim, Hyung-Seok; Lin, Terri C; Robbennolt, Shauna; Detsi, Eric; Dunn, Bruce S; Tolbert, Sarah H

    2017-06-07

    This work aims to improve the poor cycle lifetime of silicon-based anodes for Li-ion batteries by tuning microstructural parameters such as pore size, pore volume, and specific surface area in chemically synthesized mesoporous silicon. Here we have specifically produced two different mesoporous silicon samples from the magnesiothermic reduction of ordered mesoporous silica in either argon or forming gas. In situ X-ray diffraction studies indicate that samples made in Ar proceed through a Mg 2 Si intermediate, and this results in samples with larger pores (diameter ≈ 90 nm), modest total porosity (34%), and modest specific surface area (50 m 2 g -1 ). Reduction in forming gas, by contrast, results in direct conversion of silica to silicon, and this produces samples with smaller pores (diameter ≈ 40 nm), higher porosity (41%), and a larger specific surface area (70 m 2 g -1 ). The material with smaller pores outperforms the one with larger pores, delivering a capacity of 1121 mAh g -1 at 10 A g -1 and retains 1292 mAh g -1 at 5 A g -1 after 500 cycles. For comparison, the sample with larger pores delivers a capacity of 731 mAh g -1 at 10 A g -1 and retains 845 mAh g -1 at 5 A g -1 after 500 cycles. The dependence of capacity retention and charge storage kinetics on the nanoscale architecture clearly suggests that these microstructural parameters significantly impact the performance of mesoporous alloy type anodes. Our work is therefore expected to contribute to the design and synthesis of optimal mesoporous architectures for advanced Li-ion battery anodes.

  17. Surface determination of 3D confocal Raman microscopy imaging of the skin

    Science.gov (United States)

    Schleusener, J.; Carrer, V.; Patzelt, A.; Lademann, J.; Darvin, M. E.

    2017-12-01

    A surface determination method for the application of 3D confocal Raman microscopy on inhomogeneous skin sections has been presented, which is based on depth profiles of the keratin contribution of the acquired Raman spectra. The method was compared to two similar auto-focusing methods that are based on the intensity of the reflected excitation light and Raman spectra, respectively. The measurements were performed on hair follicles containing skin sections of porcine ears ex vivo. The surface determination on such samples is especially challenging due to their different molecular composition and surface inhomogeneity. An advantage of this method is molecular sensitivity, whereby only the surface of the sample will be detected and not the substrate of the microscope slide, in the case of disruptions during the processing of samples. A disadvantage of the method is the increased overall acquisition time if only the surface spectra are to be applied for 2D mapping.

  18. A method for determination of mass per unit area inhomogeneity of thin samples in XRF analysis

    International Nuclear Information System (INIS)

    Sitko, R.; Jurczyk, J.

    1999-01-01

    The authors have presented a simple method for the determination of possible inhomogeneity of thin samples in a wavedispersive XRF analysis after previous examination of intensity distribution of exciting radiation on sample's surface. Investigations were carried out using as an example microsamples of mono- and polycrystals. Samples were prepared by digesting an analysed material directly on the substrate. The obtained results have been presented in a graphical way. (author)

  19. Investigation of surface porosity measurements and compaction pressure as means to ensure consistent contact angle determinations

    DEFF Research Database (Denmark)

    Holm, René; Borkenfelt, Simon; Allesø, Morten

    2016-01-01

    for a compound is determined by its contact angle to a liquid, which in the present study was measured using the sessile drop method applied to a disc compact of the compound. Precise determination of the contact angle is important should it be used to either rank compounds or selected excipients to e.......g. increase the wetting from a solid dosage form. Since surface roughness of the compact has been suggested to influence the measurement this study investigated if the surface quality, in terms of surface porosity, had an influence on the measured contact angle. A correlation to surface porosity was observed......, however for six out of seven compounds similar results were obtained by applying a standard pressure (866MPa) to the discs in their preparation. The data presented in the present work therefore suggest that a constant high pressure should be sufficient for most compounds when determining the contact angle...

  20. Size-Dependent Specific Surface Area of Nanoporous Film Assembled by Core-Shell Iron Nanoclusters

    Directory of Open Access Journals (Sweden)

    Jiji Antony

    2006-01-01

    Full Text Available Nanoporous films of core-shell iron nanoclusters have improved possibilities for remediation, chemical reactivity rate, and environmentally favorable reaction pathways. Conventional methods often have difficulties to yield stable monodispersed core-shell nanoparticles. We produced core-shell nanoclusters by a cluster source that utilizes combination of Fe target sputtering along with gas aggregations in an inert atmosphere at 7∘C. Sizes of core-shell iron-iron oxide nanoclusters are observed with transmission electron microscopy (TEM. The specific surface areas of the porous films obtained from Brunauer-Emmett-Teller (BET process are size-dependent and compared with the calculated data.

  1. Fabrication of large-area hydrophobic surfaces with femtosecond-laser-structured molds

    Science.gov (United States)

    Wu, P. H.; Cheng, C. W.; Chang, C. P.; Wu, T. M.; Wang, J. K.

    2011-11-01

    Fast replication of large-area femtosecond-laser-induced surface micro/nanostructures on plastic parts by injection molding is demonstrated. An STAVAX steel mold insert is irradiated by femtosecond laser pulses with linear or circular polarization to form periodic-like nanostructures or nanostructure-covered conical microstructures. It was then used for the process of thermal injection molding. The process provides high-volume manufacturing means to generate hydrophobic enhanced plastic parts, which is expected to be widely used in consumables and chemical/biomedical device industries.

  2. Understanding the growth mechanism of carbon nanotubes via the ``cluster volume to surface area" model

    Science.gov (United States)

    Mandati, Sreekanth; Kunstmann, Jens; Boerrnert, Felix; Schoenfelder, Ronny; Ruemmeli, Mark; Kar, Kamal K.; Cuniberti, Gianaurelio

    2010-03-01

    The influence of mixed catalysts for the high yield production of carbon nanotubes (CNTs) has been studied systematically. Based on extensive experimental data a ``Catalyst Volume to Surface Area'' (CVSA) model was developed to understand the influence of the process parameters on the yield and CNT diameter distribution [1]. In our study, we present a refined version of the CVSA model developed by combining experiments and simulations. We discuss our current understanding of the growth mechanism and how the model might be used to increase CNT yields by using mixed catalysts.[4pt] [1] S. Tetali et al., ACS Nano (2009), DOI: 10.1021/nn9012548.

  3. Surface characteristics determining the cell compatibility of ionically cross-linked alginate gels

    International Nuclear Information System (INIS)

    Machida-Sano, Ikuko; Hirakawa, Makoto; Matsumoto, Hiroki; Kamada, Mitsuki; Ogawa, Sakito; Satoh, Nao; Namiki, Hideo

    2014-01-01

    In this study we investigated differences in the characteristics determining the suitability of five types of ion (Fe 3+ , Al 3+ , Ca 2+ , Ba 2+ and Sr 2+ )-cross-linked alginate films as culture substrates for cells. Human dermal fibroblasts were cultured on each alginate film to examine the cell affinity of the alginates. Since cell behavior on the surface of a material is dependent on the proteins adsorbed to it, we investigated the protein adsorption ability and surface features (wettability, morphology and charge) related to the protein adsorption abilities of alginate films. We observed that ferric, aluminum and barium ion-cross-linked alginate films supported better cell growth and adsorbed higher amounts of serum proteins than other types. Surface wettability analysis demonstrated that ferric and aluminum ion-cross-linked alginates had moderate hydrophilic surfaces, while other types showed highly hydrophilic surfaces. The roughness was exhibited only on barium ion-cross-linked alginate surface. Surface charge measurements revealed that alginate films had negatively charged surfaces, and showed little difference among the five types of gel. These results indicate that the critical factors of ionically cross-linked alginate films determining the protein adsorption ability required for their cell compatibility may be surface wettability and morphology. (paper)

  4. Determination of elemental in soil samples from Gebeng area using NAA technique

    International Nuclear Information System (INIS)

    Md Suhaimi Elias; Wo, Y.M.; Mohd Suhaimi Hamzah

    2016-01-01

    Rapid development and urbanization will increase number of residence and industrial area. Without proper management and control of pollution, these will give an adverse effect to environment and human life. The objective of this study to identify and quantify key contaminants into the environment of the Gebeng area as a result of industrial and human activities. Gebeng area was gazetted as one of the industrial estate in Pahang state. Assessment of elemental pollution in soil of Gebeng area base on level of concentration, enrichment factor and geo-accumulation index. The enrichment factors (EFs) were determined by the elemental rationing method, whilst the geo-accumulation index (I geo ) by comparing of current to continental crustal average concentration of element. Twenty-seven of soil samples were collected from Gebeng area. Soil samples were analysed by using Neutron Activation Analyses (NAA) technique. The obtained data showed higher concentration of iron (Fe) due to abundance in soil compared to other elements. The results of enrichment factor showed that Gebeng area have enrich with elements of As, Br, Hf, Sb, Th and U. Base on the geo-accumulation index (I geo ) classification, the soil quality of Gebeng area can be classified as class 0, (uncontaminated) to Class 3, (moderately to heavily contaminated). (author)

  5. Radioecological state of some surface water systems of contaminated areas of both Gomel and Mogilev Regions

    International Nuclear Information System (INIS)

    Datskevich, P. I.; Komissariv, F. D.; Khvale', O. D.; Basharina, L. P.; Lobach, I. L.

    1997-01-01

    The radioecological situation of different ecosystems of Belarus and their components has been analysed. Such components of the surface water ecosystems as water, suspensions, sediments and soils of water-collection areas were used for the investigation of the content of cesium 137 and strontium 90. The received data were given since 1990. The content of cesium 137 and strontium 90 in the components of water ecosystems was counted in the laboratory conditions by means of standard methods of beta radiometry, semiconductor gamma spectrometry and radiochemistry. The error of measurement of radioactivity was not higher than 25 and 35% for cesium 137 and strontium 90 accordingly. Water ecosystems were distinguished by the state of contamination of water-collection areas and hydrological parameters. These and some other reasons considered in the article influence on the character of cesium 137 and strontium 90 behaviour in water ecosystems

  6. Long term change of diurnal cycle in surface air temperature over Tokyo metropolitan area

    Science.gov (United States)

    Hara, M.; Shimada, T.

    2017-12-01

    Tokyo Metropolitan area (i.e. southern part of Kanto district) is known for one of the hottest areas in summer in Japan. Especially in Saitama prefecture (north of Tokyo), the daily maximum surface air temperature (SAT) at screen height sometimes reached in 40 C. In the last decade, the summer heat environment in Japan is getting worse, and the number of emergency transportations due to heat stroke is rapidly increasing. In this study, we evaluate regional climate change due to some factors, such as land use / land cover changes. To evaluate the regional climate change, we performed analysis of observed data and a series of past climate simulations using the Weather Research and Forecasting (WRF) model with high horizontal resolution, including an urban canopy sub-model.

  7. Dose-area product and entrance surface dose in paediatric radiography

    Energy Technology Data Exchange (ETDEWEB)

    Servomaa, A.; Komppa, T.; Parviainen, T.; Heikkilae, M. [STUK - Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2003-06-01

    Dose-area products (DAP) in paediatric radiography were measured in four university hospitals in Finland. The entrance surface dose (ESD) was calculated from the measured DAP value for each radiographic projection. The purpose was to combine the results with other European studies for development of diagnostic reference levels for paediatric X-ray examinations. The study included 740 paediatric patients, and a total of 1500 single projections were recorded, including 660 projections from extremities. Results were compared with recommended best practices and diagnostic reference levels for ESD. Ratios of DAP to ESD were studied to estimate the levels of DAP corresponding to recommended ESD reference levels. It is desirable for practical purposes that diagnostic reference levels for radiographic projections are also expressed in terms of dose-area product. (orig.)

  8. Surface Area Variability of a North-Central Tanzanian Crater Lake

    Directory of Open Access Journals (Sweden)

    Lindsey Higgins

    2016-06-01

    Full Text Available A history of modern (1973–2015 surface area variability for Lake Basotu in north-central Tanzania has been reconstructed using archived Landsat images from the dry season between June and October. This record was compared to local weather data as well as larger scale weather patterns. The lake has been in a state of decline interrupted by major flood events since the beginning of the satellite record. From 1973 to 1997, the lake area was between 0.97 km2 and 4.28 km2. Lake extent abruptly increased to 13.86 km2 in 1998, when a co-occurrence of El Niño and a positive Indian Ocean Dipole led to extensive flooding. It is hypothesized that local agricultural practices leading to soil erosion and subsequent basin sedimentation have most likely increased the sensitivity of Lake Basotu to climatic fluctuations.

  9. Temporal trends of surface urban heat islands and associated determinants in major Chinese cities.

    Science.gov (United States)

    Yao, Rui; Wang, Lunche; Huang, Xin; Niu, Zigeng; Liu, Fongfu; Wang, Qing

    2017-12-31

    There are many studies focusing on spatial variations of surface urban heat islands (SUHIs) in literature. In this study, MODIS land surface temperature (LST) data and China's Land Use/Cover Datasets (CLUDs) were used to examine the temporal trends of SUHIs in 31 major Chinese cities during 2001-2015 using three indicators: SUHI intensity (SUHII), area of the SUHI (Area SUHI ) and percentage of area with increasing SUHII (PAISUHII). Correlation analyses between SUHII and background (rural) LST (extracted from MODIS LST), vegetation coverage (reflected by MODIS EVI data) and anthropogenic heat release (reflected by nighttime light data) were performed from temporal rather than spatial perspectives. Our findings showed that the SUHII and Area SUHI in urbanized areas increased significantly in most cities in summer days, whereas they increased significantly in approximately half and more than half of the cities in summer and winter nights, respectively. In summer days, summer nights and winter nights, the PAISUHII was approximately 80% and over 50% in union areas and the 20km buffer, respectively. Correlation analyses indicated that the SUHII in stable urban areas was negatively correlated with the background LST in summer and winter days for most cities, especially in northern China. A reduction in vegetation contributed to the increasing SUHII in urbanized areas in summer days and nights. The increasing anthropogenic heat release was an important factor for increases in the SUHII in urbanized areas. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Surface buckling of black phosphorus: Determination, origin, and influence on electronic structure

    Science.gov (United States)

    Dai, Zhongwei; Jin, Wencan; Yu, Jie-Xiang; Grady, Maxwell; Sadowski, Jerzy T.; Kim, Young Duck; Hone, James; Dadap, Jerry I.; Zang, Jiadong; Osgood, Richard M.; Pohl, Karsten

    2017-12-01

    The surface structure of black phosphorus materials is determined using surface-sensitive dynamical microspot low energy electron diffraction (μ LEED ) analysis using a high spatial resolution low energy electron microscopy (LEEM) system. Samples of (i) crystalline cleaved black phosphorus (BP) at 300 K and (ii) exfoliated few-layer phosphorene (FLP) of about 10 nm thickness which were annealed at 573 K in vacuum were studied. In both samples, a significant surface buckling of 0.22 Å and 0.30 Å, respectively, is measured, which is one order of magnitude larger than previously reported. As direct evidence for large buckling, we observe a set of (for the flat surface forbidden) diffraction spots. Using first-principles calculations, we find that the presence of surface vacancies is responsible for the surface buckling in both BP and FLP, and is related to the intrinsic hole doping of phosphoresce materials previously reported.

  11. Surface water areas significantly impacted 2014 dengue outbreaks in Guangzhou, China.

    Science.gov (United States)

    Tian, Huaiyu; Huang, Shanqian; Zhou, Sen; Bi, Peng; Yang, Zhicong; Li, Xiujun; Chen, Lifan; Cazelles, Bernard; Yang, Jing; Luo, Lei; Jing, Qinlong; Yuan, Wenping; Pei, Yao; Sun, Zhe; Yue, Tianxiang; Kwan, Mei-Po; Liu, Qiyong; Wang, Ming; Tong, Shilu; Brownstein, John S; Xu, Bing

    2016-10-01

    Dengue transmission in urban areas is strongly influenced by a range of biological and environmental factors, yet the key drivers still need further exploration. To better understand mechanisms of environment-mosquito-urban dengue transmission, we propose an empirical model parameterized and cross-validated from a unique dataset including viral gene sequences, vector dynamics and human dengue cases in Guangzhou, China, together with a 36-year urban environmental change maps investigated by spatiotemporal satellite image fusion. The dengue epidemics in Guangzhou are highly episodic and were not associated with annual rainfall over time. Our results indicate that urban environmental changes, especially variations in surface area covered by water in urban areas, can substantially alter the virus population and dengue transmission. The recent severe dengue outbreaks in Guangzhou may be due to the surge in an artificial lake construction, which could increase infection force between vector (mainly Aedes albopictus) and host when urban water area significantly increased. Impacts of urban environmental change on dengue dynamics may not have been thoroughly investigated in the past studies and more work needs to be done to better understand the consequences of urbanization processes in our changing world. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Multiscale Spatial Assessment of Determinant Factors of Land Use Change: Study at Urban Area of Yogyakarta

    Science.gov (United States)

    Susilo, Bowo

    2017-12-01

    Studies of land use change have been undertaken by different researchers using various methods. Among those methods, modelling is widely utilized. Modelling land use change required several components remarked as model variables. Those represent any conditions or factors which considered relevant or have some degree of correlation to the changes of land use. Variables which have significant correlation to land use change are referred as determinant factors or driving forces. Those factors as well as changes of land use are distributed across space and therefore referred as spatial determinant factors. The main objective of the research was to examine land use change and its determinant factors. Area and location of land use change were analysed based on three different years of land use maps, which are 1993, 2000 and 2007. Spatial and temporal analysis were performed which emphasize to the influence of scale to both of analysis’s. Urban area of Yogyakarta was selected as study area. Study area covered three different districts (kabupaten), involving 20 sub districts and totally consists of 74 villages. Result of this study shows that during 14 years periods (1993 to 2007), there were about 1,460 hectares of land use change had been taken place. Dominant type of land use change is agricultural to residential. The uses of different spatial and temporal scale in analysis were able to reveal different factors related to land use change. In general, factors influencing the quantities of land use change in the study area were population growth and the availability of land. The use of data with different spatial resolution can reveal the presence of various factors associated with the location of the change. Locations of land use change were influenced or determined by accessibility factors.

  13. Segmental equivalent temperature determined by means of a thermal manikin: A method for correcting errors due to incomplete contact of the body with a surface

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Janieas, N.R.D.J.; Silva, M.C.G.

    2004-01-01

    The segmental equivalent temperature determined by means of a thermal manikin is often correlated with the local thermal sensation of people and is used for indoor environment assessment. It is also used to assess performance of heated/cooled/ventilated car seats, etc. However, the body...... of the thermal manikins used at present is not as flexible as the human body and is divided into body segments with a surface area that differs from that of the human body in contact with a surface. The area of the segment in contact with a surface will depend on the shape and flexibility of the surface....... This will affect the accuracy in determination of the segmental equivalent temperature, and will result in incorrect assessment. This paper presents a method for correction of the segmental equivalent temperature for the above effects. Improvement in determination of the segmental equivalent temperature...

  14. Two-dimensional echocardiographic right ventricle measurements adjusted to body mass index and surface area in a normal population.

    Science.gov (United States)

    Eslami, Masood; Larti, Farnoush; Larry, Mehrdad; Molaee, Parisa; Badkoobeh, Roya Sattarzadeh; Tavoosi, Anahita; Safari, Saeed; Parsa, Amir Farhang Zand

    2017-05-01

    To determine reference echocardiographic values in a normal population and assess their correlation with body mass index (BMI) and body surface area. An expert cardiologist performed two-dimensional echocardiography with triplicate right ventricle (RV) size measurements in 80 subjects with normal heart condition. Results were correlated with anthropometric data. Base-to-apex length in four-chamber view (RVD3) and above-pulmonic valve in short-axis view in males, as well as mid-RV diameter in standard four-chamber view (RVD), basal RV diameter, and mid RV diameter in RV-focused four-chamber view in females, were significantly correlated with BMI. All RV variables were significantly correlated with BMI in 20-30-year-old subjects. All RV variables except RVD3 and above-aortic valve in short-axis view (proximal) were significantly correlated with BMI in 35-55-year-old subjects. All RV parameters were significantly correlated with body surface area, except for RVD and in 20-35-year-old subjects. RV echocardiographic values must be adjusted to anthropometric characteristics for proper diagnosis and management of cardiac disorders. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:204-210, 2017. © 2016 Wiley Periodicals, Inc.

  15. Impacts of urban land-surface forcing on ozone air quality in the Seoul metropolitan area

    Directory of Open Access Journals (Sweden)

    Y.-H. Ryu

    2013-02-01

    Full Text Available Modified local meteorology owing to heterogeneities in the urban–rural surface can affect urban air quality. In this study, the impacts of urban land-surface forcing on ozone air quality during a high ozone (O3 episode in the Seoul metropolitan area, South Korea, are investigated using a high-resolution chemical transport model (CMAQ. Under fair weather conditions, the temperature excess (urban heat island significantly modifies boundary layer characteristics/structures and local circulations. The modified boundary layer and local circulations result in an increase in O3 levels in the urban area of 16 ppb in the nighttime and 13 ppb in the daytime. Enhanced turbulence in the deep urban boundary layer dilutes pollutants such as NOx, and this contributes to the elevated O3 levels through the reduced O3 destruction by NO in the NOx-rich environment. The advection of O3 precursors over the mountains near Seoul by the prevailing valley-breeze circulation in the mid- to late morning results in the build-up of O3 over the mountains in conjunction with biogenic volatile organic compound (BVOC emissions there. As the prevailing local circulation in the afternoon changes to urban-breeze circulation, the O3-rich air masses over the mountains are advected over the urban area. The urban-breeze circulation exerts significant influences on not only the advection of O3 but also the chemical production of O3 under the circumstances in which both anthropogenic and biogenic (natural emissions play important roles in O3 formation. As the air masses that are characterized by low NOx and high BVOC levels and long OH chain length are advected over the urban area from the surroundings, the ozone production efficiency increases in the urban area. The relatively strong vertical mixing in the urban boundary layer embedded in the

  16. Synthesis of silica aerogel monoliths with controlled specific surface areas and pore sizes

    Science.gov (United States)

    Gao, Bingying; Lu, Shaoxiang; Kalulu, Mulenga; Oderinde, Olayinka; Ren, Lili

    2017-07-01

    To replace traditional preparation methods of silica aerogels, a small-molecule 1,2-epoxypropane (PO) has been introduced into the preparation process instead of using ammonia as the cross-linking agent, thus generating a lightweight, high porosity, and large surface area silica aerogel monolithic. We put forward a simple solution route for the chemical synthesis of silica aerogels, which was characterized by scanning electron microscopy (SEM), TEM, XRD, FTIR, thermogravimetric analysis (TGA) and the Brunauer-Emmett-Teller (BET) method In this paper, the effect of the amount of PO on the microstructure of silica aerogels is discussed. The BET surface areas and pore sizes of the resulting silica aerogels can be freely adjusted by changing the amount of PO, which will be helpful in promoting the development of silica aerogels to fabricate other porous materials with similar requirements. We also adopted a new organic solvent sublimation drying (OSSD) method to replace traditional expensive and dangerous drying methods such as critical point drying and freeze drying. This simple approach is easy to operate and has good repeatability, which will further facilitate actual applications of silica aerogels.

  17. Porous boron nitride with a high surface area: hydrogen storage and water treatment.

    Science.gov (United States)

    Li, Jie; Lin, Jing; Xu, Xuewen; Zhang, Xinghua; Xue, Yanming; Mi, Jiao; Mo, Zhaojun; Fan, Ying; Hu, Long; Yang, Xiaojing; Zhang, Jun; Meng, Fanbin; Yuan, Songdong; Tang, Chengchun

    2013-04-19

    We report on the synthesis of high-quality microporous/mesoporous BN material via a facile two-step approach. An extremely high surface area of 1687 m(2) g(-1) and a large pore volume of 0.99 cm(3) g(-1) have been observed in the synthesized BN porous whiskers. The formation of the porous structure was attributed to the group elimination of organic species in a BN precursor, melamine diborate molecular crystal. This elimination method maintained the ordered pore structure and numerous structural defects. The features including high surface area, pore volume and structural defects make the BN whiskers highly suitable for hydrogen storage and wastewater treatment applications. We demonstrate excellent hydrogen uptake capacity of the BN whiskers with high weight adsorption up to 5.6% at room temperature and at the relatively low pressure of 3 MPa. Furthermore, the BN whiskers also exhibit excellent adsorption capacity of methyl orange and copper ions, with the maximum removal capacity of 298.3 and 373 mg g(-1) at 298 K, respectively.

  18. High-Surface-Area Nitrogen-Doped Reduced Graphene Oxide for Electric Double-Layer Capacitors.

    Science.gov (United States)

    Youn, Hee-Chang; Bak, Seong-Min; Kim, Myeong-Seong; Jaye, Cherno; Fischer, Daniel A; Lee, Chang-Wook; Yang, Xiao-Qing; Roh, Kwang Chul; Kim, Kwang-Bum

    2015-06-08

    A two-step method consisting of solid-state microwave irradiation and heat treatment under NH3 gas was used to prepare nitrogen-doped reduced graphene oxide (N-RGO) with a high specific surface area (1007 m(2)  g(-1) ), high electrical conductivity (1532 S m(-1) ), and low oxygen content (1.5 wt %) for electrical double-layer capacitor applications. The specific capacitance of N-RGO was 291 F g(-1) at a current density of 1 A g(-1) , and a capacitance of 261 F g(-1) was retained at 50 A g(-1) , which indicated a very good rate capability. N-RGO also showed excellent cycling stability and preserved 96 % of the initial specific capacitance after 100 000 cycles. Near-edge X-ray absorption fine-structure spectroscopy results provided evidenced for the recovery of π conjugation in the carbon networks with the removal of oxygenated groups and revealed chemical bonding of the nitrogen atoms in N-RGO. The good electrochemical performance of N-RGO is attributed to its high surface area, high electrical conductivity, and low oxygen content. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Particle size and surface area effects on the thin-pulse shock initiation of Diaminoazoxyfurazan (DAAF)

    Science.gov (United States)

    Burritt, Rosemary; Francois, Elizabeth; Windler, Gary; Chavez, David

    2017-06-01

    Diaminoazoxyfurazan (DAAF) has many of the safety characteristics of an insensitive high explosive (IHE): it is extremely insensitive to impact and friction and is comparable to triaminotrinitrobezene (TATB) in this way. Conversely, it demonstrates many performance characteristics of a Conventional High Explosive (CHE). DAAF has a small failure diameter of about 1.25 mm and can be sensitive to shock under the right conditions. Large particle sized DAAF will not initiate in a typical exploding foil initiator (EFI) configuration but smaller particle sizes will. Large particle sized DAAF, of 40 μm, was crash precipitated and ball milled into six distinct samples and pressed into pellets with a density of 1.60 g/cc (91% TMD). To investigate the effect of particle size and surface area on the direct initiation on DAAF multiple threshold tests were preformed on each sample of DAAF in different EFI configurations, which varied in flyer thickness and/or bridge size. Comparative tests were performed examining threshold voltage and correlated to Photon Doppler Velocimetry (PDV) results. The samples with larger particle sizes and surface area required more energy to initiate while the smaller particle sizes required less energy and could be initiated with smaller diameter flyers.

  20. Adsorption of naphthalene onto a high-surface-area carbon from waste ion exchange resin.

    Science.gov (United States)

    Shi, Qianqian; Li, Aimin; Zhu, Zhaolian; Liu, Bing

    2013-01-01

    A high-surface-area carbon (KC-1) was prepared from waste polystyrene-based ion exchange resin by KOH activation and used for naphthalene adsorption. The carbon exhibited a good hydrophobic nature with developed porous structure, favoring the adsorption of organic compounds. The Brunauer-Emmett-Teller surface area and total pore volume of KC-1 were 3442.2 and 1.68 cm3/g, respectively, which can be compared with those of KOH-activated carbons prepared from other precursors. Batch experiments were carried out to investigate the adsorption of naphthalene onto KC-1. The equilibrium data were analyzed by the Langmuir, Freundlich, and Polanyi-Manes isotherms and agreed with the Polanyi-Manes Model. The adsorption of naphthalene depended greatly on the porosity of the carbon, and the dispersive interactions between naphthalene and carbon could be relatively weak. The pH variation in aqueous solution had little effect on the adsorption process. The equilibrium time for 0.04 g/L of carbon dose was around 5 hr. Different models were used to evaluate the kinetic data and the pseudo second-order model was suitable to describe the kinetic process of naphthalene adsorption onto KC-1. Regeneration of spent carbon could be carried out effectively by alcohol treatment. The results indicated that KC-1 was a promising adsorbent for the removal of polycyclic aromatic hydrocarbons from aqueous solutions.