WorldWideScience

Sample records for wood moisture moisture

  1. Moisture Transport in Wood

    DEFF Research Database (Denmark)

    Astrup, Thomas; Hansen, Kurt Kielsgaard; Hoffmeyer, Preben

    2005-01-01

    Modelling of moisture transport in wood is of great importance as most mechanical and physical properties of wood depend on moisture content. Moisture transport in porous materials is often described by Ficks second law, but several observations indicate that this does not apply very well to wood....... Recently at the Technical University of Denmark, Department of Civil Engineering, a new model for moisture transport in wood has been developed. The model divides the transport into two phases, namely water vapour in the cell lumens and bound water in the cell walls....

  2. Moisture transport in coated wood

    NARCIS (Netherlands)

    Meel, P.A. van; Erich, S.J.F.; Huinink, H.P.; Kopinga, K.; Jong, J. DE; Adan, O.C.G.

    2011-01-01

    Moisture accumulation inside wood causes favorable conditions for decay. Application of a coating alters the moisture sorption of wood and prevents accumulation of moisture. This paper presents the results of a nuclear magnetic resonance (NMR) study on the influence of a coating on the moisture

  3. Moisture relations and physical properties of wood

    Science.gov (United States)

    Samuel V. Glass; Samuel L. Zelinka

    2010-01-01

    Wood, like many natural materials, is hygroscopic; it takes on moisture from the surrounding environment. Moisture exchange between wood and air depends on the relative humidity and temperature of the air and the current amount of water in the wood. This moisture relationship has an important influence on wood properties and performance. Many of the challenges of using...

  4. Moisture-driven fracture in solid wood

    DEFF Research Database (Denmark)

    Larsen, Finn; Ormarsson, Sigurdur; Olesen, John Forbes

    2011-01-01

    Moisture-induced fractures in solid timber create considerable problems for both building industries and sawmills. Cracks caused by kiln-drying of solid timber are extremely difficult to predict. This paper reports on experiments concerned with methods of reducing cracks in wood and with the crac......Moisture-induced fractures in solid timber create considerable problems for both building industries and sawmills. Cracks caused by kiln-drying of solid timber are extremely difficult to predict. This paper reports on experiments concerned with methods of reducing cracks in wood...... process, suggesting that sealing the ends of timber logs while in the green moisture state could considerably reduce the development of end-cracks. The initial moisture content and the shrinkage properties of the wood varied markedly from pith to bark. The importance of taking material inhomogeneities...... into account when modelling crack propagation in solid wood is emphasized. © 2011 Taylor & Francis....

  5. Variation of moisture content of some varnished woods in indoor climatic conditions

    Directory of Open Access Journals (Sweden)

    Kemal Üçüncü

    2017-11-01

    Full Text Available In this study, moisture change of varnished wood of black poplar (Populus nigra and yellow pine (Pinus silvestris L. used in indoor climate conditions with central heating in Trabzon (Turkey were investigated. 300 mm length wood specimens, with cross section of 12.5 mm in tangential and in radial and with the square sections of 25mm and 50 mm, were obtained from two species grown in Kanuni Campus of the Karadeniz Technical University. In this research, un-varnished wood samples were also used for reference. The wood moisture content was determined by the weighing method, the wood equilibrium moisture content by the Hailwood-Horrobin equation, and the relative humidity in the indoor climatic conditions by humid air thermodynamic principles. As a result; it was observed that the moisture content of varnished wood samples has a strong relationship with equilibrium moisture content, temperature and relative humidity. It was found that the moisture content of varnished woods was higher than the moisture content of un-varnished woods in the same climatic conditions. It was observed that the difference between the monthly average moisture content was lower in varnished woods in proportion to un-varnished woods. According to these results, it can be indicated that it would be more appropriate to select higher moisture content in the drying of wood than the equilibrium moisture content. Such an application would also reduce drying costs. Further, it can be recommended to use varnished wood in various applications because the low change range of average moisture content can affect the swelling or shrinking of wood.

  6. A new method of determining moisture gradient in wood

    Science.gov (United States)

    Zhiyong Cai

    2008-01-01

    Moisture gradient in wood and wood composites is one of most important factors that affects both physical stability and mechanical performance. This paper describes a method for measuring moisture gradient in lumber and engineering wood composites as it varies across material thickness. This innovative method employs a collimated radiation beam (x rays or [gamma] rays...

  7. A Unilateral Nuclear Magnetic Resonance Sensor for Nondestructive Wood Moisture Measurements

    Directory of Open Access Journals (Sweden)

    YU Deng-jie

    2017-12-01

    Full Text Available An unilateral nuclear magnetic resonance (UMR sensor was designed to measure wood moisture nondestructively. The sensor consisted of a unilateral magnet, an anti-eddy current module, a radiofrequency (RF coil and an impedance matching and tuning circuit. The sensor produced a static magnetic field of 71.1 mT (resonant frequency:3.027 MHz in a 50 mm×50 mm plane locating 75 mm above the sensor's surface. Preliminary nondestructive measurement of wood moisture was carried out with the sensor. The moisture distribution in the radical direction of a cylindrical wood sample was scanned. Variations in transverse relaxation time (T2 from the bark to core were obtained. Evaporation of moisture during wood drying was also measured with the UMR sensor. Experimental results showed that:the peak of long T2 component in the T2 spectrum moved to left and the peak integral area decreased gradually during drying. The integral area was proportional to the moisture content of the sample. The work presents a portable UMR device for wood research which may potentially be used for nondestructive moisture measurement on living trees in situ.

  8. Theoretical analysis of moisture transport in wood as an open porous hygroscopic material

    DEFF Research Database (Denmark)

    Hozjan, Tomaz; Svensson, Staffan

    2010-01-01

    Moisture transport in an open porous hygroscopic material such as wood is a complex system of coupled processes. For seasoned wood in natural climate three fully coupled processes active in the moisture transport are readily identified: (1) diffusion of vapor in pores; (2) phase change from one...... state to another, also called moisture sorption; and (3) diffusion of bound water in wood tissue (in the cell wall). A mathematical model for predicting moisture transport in wood for a given condition must at least consider the dominating active processes simultaneously to be considered accurate...... of the three processes on the outcome of the coupled model. Least significant is the bound water diffusion. Based on the results from the sensitivity analyses, a simplified model for moisture transport in wood is proposed....

  9. Moisture Sorption in Artificially aged wood-plastic composites

    Science.gov (United States)

    B. Kristoffer Segerholm; Rebecca E. Ibach; Magnus E.P. Wålinder

    2012-01-01

    Moisture sorption in wood-plastic composites (WPCs) affects their durability and dimensional stability. In certain outdoor exposures, the moisture properties of WPCs are altered due to e.g. cracks induced by swelling and shrinkage of the components, as well as UV degradation or biological attack. The aim of this work was to study the effect of different artificial...

  10. Instrument for measuring moisture in wood chips

    Energy Technology Data Exchange (ETDEWEB)

    Werme, L

    1980-06-01

    A method to determine the moisture content in wood chips, in batch and on-line, has been investigated. The method can be used for frozen and non frozen chips. Samples of wood chips are thawn and dryed with microwaves. During the drying the sample is weighed continously and the rate of drying is measured. The sample is dried t 10 percent moisture content. The result is extrapolated to the drying rate zero. The acccuracy at the method is 1.6 to 1.7 percent for both frozen and non frozen chips. The accuracy of the method is considered acceptable, but sofisticated sampling equipment is necessary. This makes the method too complex to make the instrument marketable.

  11. Equilibrium moisture content of wood at different temperature/moisture conditions in the cladding of wooden constructions and in the relation to their reliability and service life

    Directory of Open Access Journals (Sweden)

    Zdeňka Havířová

    2010-01-01

    Full Text Available One of the natural properties of wood and wood-based materials is their soaking capacity (hy­gro­sco­pi­ci­ty. The moisture content of wood and building constructions of wood and wood based materials significantly influences the service life and reliability of these constructions and buildings. The equilibrium weight moisture content of built-in wood corresponding to temperature/moisture conditions inside the cladding has therefore a decisive influence on the basic requirements placed on building constructions. The wood in wooden frame cladding changes its moisture content depending on temperature and moisture conditions of the environment it is built into. The water vapor condensation doesn’t necessarily have to occur right in the wooden framework of the cladding for the equilibrium moisture content to rise over the level permissible for the reliable function of a given construction. In spite of the fact that the common heat-technical assessment cannot be considered fully capable of detecting the effects of these factors on the functional reliability of wood-based constructions and buildings, an extension has been proposed of the present method of design an assessment of building constructions according to the ČSN 73 0540 standard regarding the interpretation of equilibrium moisture content in relation to the temperature/moisture conditions and their time behavior inside a construction.

  12. Moisture measurement in wood, wood-based materials and building materials - a literature review

    International Nuclear Information System (INIS)

    Kober, A.; Mehlhorn, L.; Plinke, B.

    1989-10-01

    Methods of moisture measurement in solid substances, especially on wood, wood-based materials and building materials were examined and evaluated according to the literature available. The question was which methods of examining the moisture distribution in building elements at climate loading offer the best accuracy and spatial resolution as well as which methods are the most appropriate at present and in future for the solution of measurement problems in the wood and wood-based industry. The most common methods are electric measurement methods which are utilizing either the moisture-depending conductivity or the dielectric constant or the reflectivity of the material for infrared radiation but they offer only a limited accuracy. The same is valid for the rarely used microwave methods or X-ray and NMR tomography. Simple electric methods will further on play an important role in the industrial process measuring technique. For the examination of building elements, methods using nuclear radiation still offer possibilities for a further development. (orig.) With 207 refs., 13 figs [de

  13. Equilibrium moisture content of wood at different temperature/moisture conditions in the cladding of wooden constructions and in the relation to their reliability and service life

    OpenAIRE

    Zdeňka Havířová; Pavel Kubů

    2010-01-01

    One of the natural properties of wood and wood-based materials is their soaking capacity (hy­gro­sco­pi­ci­ty). The moisture content of wood and building constructions of wood and wood based materials significantly influences the service life and reliability of these constructions and buildings. The equilibrium weight moisture content of built-in wood corresponding to temperature/moisture conditions inside the cladding has therefore a decisive influence on the basic requirements placed on bui...

  14. Service Life Prediction of Wood Claddings by in-situ Measurement of Wood Moisture Content

    DEFF Research Database (Denmark)

    Engelund, Emil Tang; Lindegaard, Berit; Morsing, Niels

    2009-01-01

    of wood moisture are done by in-situ resistance moisture meters (Lindegaard and Morsing 2006). The aim is that the test should form the basis of evaluation of the maintenance requirements and the prediction of service life of the surface treatment and the wood/construction. At the moment 60 test racks...... are exposed. This study examines the data from the first five years of outdoor exposure using data from a test rack with a water-borne acrylic coating and a test rack with ICP coating for case studies. The moisture content data was converted into weekly average and weekly variation values which gave a deeper...

  15. Controlling moisture content of wood samples using a modified soil-pan decay method

    Science.gov (United States)

    Jerrold E. Winandy; Simon F. Curling; Patricia K. Lebow

    2005-01-01

    In wood, the threshold level below which decay cannot occur varies with species or type of wood product and other factors such as temperature, humidity, and propensity of exposure or service-use to allow rain-induced wetting and subsequent drying. The ability to control wood moisture content (MC) during laboratory decay testing could allow research on the moisture...

  16. Influence of moisture content of combusted wood on the thermal efficiency of a boiler

    Science.gov (United States)

    Dzurenda, Ladislav; Banski, Adrián

    2017-03-01

    In the paper the influence of moisture content of wood on the heat losses and thermal efficiency of a boiler is analysed. The moisture content of wood has a negative effect, especially on flue gas loss. The mathematical dependence of the thermal efficiency of a boiler is presented for the following boundary conditions: the moisture content of wood 10-60%, range of temperatures of emitted flue gases from the boiler into the atmosphere 120-200 C, the emissions meeting the emission standards: carbon monoxide 250 mgm-3, fly ash 50 mgm-3 and the heat power range 30-100%.

  17. Influence of moisture content of combusted wood on the thermal efficiency of a boiler

    Directory of Open Access Journals (Sweden)

    Dzurenda Ladislav

    2017-03-01

    Full Text Available In the paper the influence of moisture content of wood on the heat losses and thermal efficiency of a boiler is analysed. The moisture content of wood has a negative effect, especially on flue gas loss. The mathematical dependence of the thermal efficiency of a boiler is presented for the following boundary conditions: the moisture content of wood 10-60%, range of temperatures of emitted flue gases from the boiler into the atmosphere 120-200 C, the emissions meeting the emission standards: carbon monoxide 250 mgm−3, fly ash 50 mgm−3 and the heat power range 30-100%.

  18. Moisture Performance of Energy-Efficient and Conventional Wood-Frame Wall Assemblies in a Mixed-Humid Climate

    Science.gov (United States)

    Samuel Glass; Vladimir Kochkin; S. Drumheller; Lance Barta

    2015-01-01

    Long-term moisture performance is a critical consideration for design and construction of building envelopes in energy-efficient buildings, yet field measurements of moisture characteristics for highly insulated wood-frame walls in mixed-humid climates are lacking. Temperature, relative humidity, and moisture content of wood framing and oriented strand board (OSB)...

  19. Determination of moisture content gradient in wood by gamma-ray attenuation technique

    International Nuclear Information System (INIS)

    Aguiar, O.; Barros Ferraz, E.S. de

    1981-01-01

    A new methodology for determining water content gradients in wood was developed. It was based on the low energy gamma ray attenuation. Two equations were proposed for determining wood water content, below and above the fiber saturation point. A series of measurents of moisture content gradients in wood samples of Pinus oocarpa was made, during drying in an environment with controlled relative humidity and temperature. The water cntent gradients determination was quick, non-destructive and presented sensitivity and accuracy in moisture content range from 9% to 150%. Aspects of the application of this methodology in water diffusion and flow studies in wood are discussed. (Author) [pt

  20. Experimental study of non-steady state moisture diffusional flow in wood

    International Nuclear Information System (INIS)

    Ayensu, A.

    1992-10-01

    Experiments have been conducted to verify the suitability of Fick's second law to describe moisture flow in wood. The moisture content change with time were plotted for absorption and desorption, and it was observed that these variations follow the same trend as modelled on the computer. The mean integral diffusion coefficient D-bar for the wood species were calculated on the basis of Boltzmann's solution of Fick's second law, D-bar ranges from 2.0 x 10 -3 cm 2 /s to 4.2 x 10 -3 cm 2 /s for both absorption and desorption. (author). 5 refs, 4 figs, 2 tabs

  1. Corrosion of Embedded Metals in Wood: An Overview of Recent Research with Implications for building moisture design

    Science.gov (United States)

    Samuel L. Zelinka

    2013-01-01

    ASHRAE Standard 160, Criteria for Moisture-Control Design Analysis in Buildings, specifies moisture design criteria in buildings to prevent moisture damage such as fungal activity and corrosion. While there has been much research on mold and decay fungi in wood buildings, it is often overlooked that wet wood is corrosive to the metal screws...

  2. Experimental study of moisture-driven distortion and fracture in solid wood

    DEFF Research Database (Denmark)

    Larsen, Finn; Ormarsson, Sigurdur; Olesen, John Forbes

    2010-01-01

    Moisture-induced fracture and lack of shape stability in solid wood products are well known problems to the saw-milling and building industries. Cracks that initiate during the drying process may cause severe material losses and the building industry may be forced to use alternative building....... An experimental study has been performed to reveal the cracking behaviour of Norway spruce during drying from green moisture content down to equilibrium moisture content (EMC) at a temperature of 22-24°C and a RH of 64%. The moisture related strains and crack widths were measured with a digital image correlation...... than the thinner ones (15 mm) and the crack patterns developed differently. For the thicker discs the early cracks which may partly be caused by the moisture gradient in the longitudinal direction of the log, closed and became invisible later during the drying process. This indicates that sealing...

  3. The effect of moisture content on the corrosion of fasteners embedded in wood subjected to alkaline copper quaternary treatment

    International Nuclear Information System (INIS)

    Zelinka, Samuel L.; Glass, Samuel V.; Derome, Dominique

    2014-01-01

    Highlights: • We examine the dependence of metal corrosion on wood moisture content. • Corrosion of steel and galvanized steel in treated wood were measured. • Corrosion products were analyzed across moisture contents using X-ray diffraction. • The corrosion rate has a sigmoidal dependence on moisture content. • The data herein can be used to improve combined hygrothermal–corrosion models. - Abstract: This paper characterizes the corrosion rate of embedded fasteners as a function of wood moisture content using gravimetric and electrochemical measurements. The results indicated that the corrosion rate increased with moisture content before reaching a plateau. The phases present in the corrosion products, as analyzed using X-ray diffraction, are generally consistent with previous work. Uniform corrosion was observed for all fasteners and all conditions except steel fasteners embedded in water-saturated wood. Data of dependence of corrosion rate on moisture content, presented herein, are necessary to ensure the accuracy of combined hygrothermal/corrosion models used to predict durability of wood structures

  4. EFFECTS OF BURN RATE, WOOD SPECIES, MOISTURE CONTENT AND WEIGHT OF WOOD LOADED ON WOODSTOVE EMISSIONS

    Science.gov (United States)

    The report gives results of tests of four woodstove operating parameters (burn rate, wood moisture, wood load, and wood species) at two levels each using a half factorial experimental test design to determine statistically significant effects on the emission components CO, CO2, p...

  5. Wood moisture monitoring during log house thermal insulation mounting

    Directory of Open Access Journals (Sweden)

    Pavla Kotásková

    2011-01-01

    Full Text Available The current designs of thermal insulation for buildings concentrate on the achievement of the required heat transmission coefficient. However, another factor that cannot be neglected is the assessment of the possible water vapour condensation inside the construction. The aim of the study was to find out whether the designed modification of the cladding structure of an existing log house will or will not lead to a risk of possible water vapour condensation in the walls after an additional thermal insulation mounting. The condensation could result in the increase in moisture of the walls and consequently the constructional timber, which would lead to the reduction of the timber construction strength, wood degradation by biotic factors – wood-destroying insects, mildew or wood-destroying fungi. The main task was to compare the theoretically established values of moisture of the constructional timber with the values measured inside the construction using a specific example of a thermal insulated log house. Three versions of thermal insulation were explored to find the solution of a log house reconstruction which would be the optimum for living purposes. Two versions deal with the cladding structure with the insulation from the interior, the third version deals with an external insulation.In a calculation model the results can be affected to a great degree by input values (boundary conditions. This especially concerns the factor of vapour barrier diffusion resistance, which is entered in accordance with the producer’s specifications; however, its real value can be lower as it depends on the perfectness and correctness of the technological procedure. That is why the study also includes thermal technical calculations of all designed insulation versions in the most unfavourable situation, which includes the degradation of the vapour barrier down to 10% efficiency, i.e. the reduction of the diffusion resistance factor to 10% of the original value

  6. Effects of processing method and moisture history on laboratory fungal resistance of wood-HDPE composites.

    Science.gov (United States)

    Craig M. Clemons; Rebecca E. Ibach

    2004-01-01

    The purpose of this study was to clarify the effects of composite processing and moisture sorption on laboratory fungal resistance of wood-plastic composites. A 2-week water soaking or cyclic boiling-drying procedure was used to infuse moisture into composites made from high-density polyethylene filled with 50 percent wood flour and processed by extrusion, compression...

  7. A new Model Applicable for Finite Element Simulations of Moisture Transport in Wood

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lund; Svensson, Staffan; Damkilde, Lars

    2006-01-01

    The moisture content in wood near the surface depends not only on the current relative humidity in the ambient air but also on preceeding variations. This hysteresis phenomenon of sorption implies in worst case that the moisture content for a given relative humidity may deviate 30-35%. Current...

  8. Method to estimate the internal stresses due to moisture in wood using transmission properties of microwaves

    International Nuclear Information System (INIS)

    Takemura, T.; Taniguchi, T.

    2004-01-01

    The purpose of this paper is to offer a new method for detecting stress in wood due to moisture along the lines of a theory reported previously. According to the theory, the stress in wood could be estimated from the moisture content of the wood and the power voltage of a microwave moisture meter (i.e., attenuation of the projected microwave). This seems to suggest a possibility of utilizing microwaves in the field of stress detection. To develop such an idea, the stress formulas were initially modified to the form of an uni-variable function of power voltage, and the application method of the formulas to detection was tried. Finally, these results were applied to the data of sugi (Cryptomeria japonica) lumber in the previous experiment. The estimated strains showed fairly good agreement with those observed. It could be concluded from this study that the proposed method might be available for detecting stress in wood due to moisture

  9. New method measures moisture and true dry mass

    International Nuclear Information System (INIS)

    Frank, H.

    The moisture content of wood can be determined by measuring the nuclear magnetic resonance of free water hydrogen atoms in wood. Nanassy studied NMR curves for six types of wood and obtained the calibration curve by reducing the moisture content in steps by 4% moisture down to ca. 1% moisture and then by gradually wetting the wood. The initial material was fresh wood. For each step he measured the intensity of the free water hydrogen signal. If the sample weight is known the dry matter content (dry weight) and moisture content of the sample can be derived from the measured NMR signal. (J.P.)

  10. Internal and external moisture transport resistance during non-stationary adsorption of moisture into wood

    OpenAIRE

    Bučar, Bojan

    2007-01-01

    The assumption that non-stationary sorption processes associated with wood canbe evaluated by analysis of their transient system response to the disturbance developed is undoubtedly correct. In general it is, in fact, possible to obtain by time analysis of the transient phenomenon - involving the transition into an arbitrary new state of equilibrium - all data required for a credible evaluation of the observed system. Evaluation of moisture movement during drying or moistening requires determ...

  11. On the influence of moisture and load variations on the strength behavior of wood

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    2005-01-01

    Abstract: It is demonstrated in this paper that the influence of moisture- and load variations on lifetime and residual strength (re-cycle strength) of wood can be considered by theories previously developed by the author. The common, controlling factor is creep, which can be modified very easily...... by introducing a special moisture dependent relaxation time in the well-known Power-Law creep expression. Because basic failure mechanisms in wood are invariant with respect to loading modes, it is suggested that a number of methods used in design of wood structures can be generalized/simplified to apply...

  12. The vibrational properties of Chinese fir wood during moisture sorption process

    Science.gov (United States)

    Jiali Jiang; Jianxiong Lu; Zhiyong Cai

    2012-01-01

    The vibrational properties of Chinese fir (Cunninghamia lanceolata) wood were investigated in this study as a function of changes in moisture content (MC) and grain direction. The dynamic modulus of elasticity (DMOE) and logarithmic decrement σ were examined using a cantilever beam vibration testing apparatus. It was observed that DMOE and 6 of wood vaned...

  13. Theoretical-and experimental analysis of the errors involved in the wood moisture determination by gamma-ray attenuation

    International Nuclear Information System (INIS)

    Aguiar, O.

    1983-01-01

    The sources of errors in wood moisture determination by gamma-ray attenuation were sought. Equations were proposed for determining errors and for ideal sample thickness. A series of measurements of moisture content in wood samples of Pinus oocarpa was made and the experimental errors were compared with the theoretical errors. (Author) [pt

  14. A revised multi-Fickian moisture transport model to describe non-Fickian effects in wood

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lund; Damkilde, Lars; Svensson, Staffan

    2007-01-01

    This paper presents a study and a refinement of the sorption rate model in a so-called multi-Fickian or multi-phase model. This type of model describes the complex moisture transport system in wood, which consists of separate water vapor and bound-water diffusion interacting through sorption...... sorption allow a simplification of the system to be modeled by a single Fickian diffusion equation. To determine the response of the system, the sorption rate model is essential. Here the function modeling the moisture-dependent adsorption rate is investigated based on existing experiments on thin wood...

  15. Moisture Performance of Energy-Efficient and Conventional Wood-Frame Wall Assemblies in a Mixed-Humid Climate

    Directory of Open Access Journals (Sweden)

    Samuel V. Glass

    2015-07-01

    Full Text Available Long-term moisture performance is a critical consideration for design and construction of building envelopes in energy-efficient buildings, yet field measurements of moisture characteristics for highly insulated wood-frame walls in mixed-humid climates are lacking. Temperature, relative humidity, and moisture content of wood framing and oriented strand board (OSB structural panel sheathing were measured over a period from mid-November 2011 through March 2013 in both north- and south-facing orientations in test structures near Washington, DC, USA. Wall configurations varied in exterior cladding, water-resistive barrier, level of cavity insulation, presence of exterior continuous insulation, and interior vapor retarder. The combination of high interior humidity and high vapor permeance of painted gypsum board led to significant moisture accumulation in OSB sheathing during winter in walls without a vapor retarder. In contrast, wintertime moisture accumulation was not significant with an interior kraft vapor retarder. Extruded polystyrene exterior insulation had a predictable effect on wall cavity temperature but a marginal impact on OSB moisture content in walls with vinyl siding and interior kraft vapor retarder. Hygrothermal simulations approximately captured the timing of seasonal changes in OSB moisture content, differences between north- and south-facing walls, and differences between walls with and without an interior kraft vapor retarder.

  16. Evaluation of moisture content distribution in wood by soft X-ray imaging

    International Nuclear Information System (INIS)

    Tanaka, T.; Avramidis, S.; Shida, S.

    2009-01-01

    A technique for nondestructive evaluation of moisture content distribution of Japanese cedar (sugi) during drying using a newly developed soft X-ray digital microscope was investigated. Radial, tangential, and cross-sectional samples measuring 100 x 100 x 10 mm were cut from green sugi wood. Each sample was dried in several steps in an oven and upon completion of each step, the mass was recorded and a soft X-ray image was taken. The relationship between moisture content and the average grayscale value of the soft X-ray image at each step was linear. In addition, the linear regressions overlapped each other regardless of the sample sections. These results showed that soft X-ray images could accurately estimate the moisture content. Applying this relationship to a small section of each sample, the moisture content distribution was estimated from the image differential between the soft X-ray pictures obtained from the sample in question and the same sample in the oven-dried condition. Moisture content profiles for 10-mm-wide parts at the centers of the samples were also obtained. The shapes of the profiles supported the evaluation method used in this study

  17. Moisture evaluation of wood material using GPR with WARR method - COST Action TU1208

    Science.gov (United States)

    Reci, Hamza; Sbart'i, Zoubir Mehdi; Pajewski, Lara; Marciniak, Marian

    2016-04-01

    This work deals with the study of the sensitivity of GPR electromagnetic waves to moisture variation in wood material in relation with the direction of fibers and polarization of Electromagnetic field. The relations between relative permittivity and moisture content and the amplitude attenuation with distance was a target study using the direct waves in Wide Angle Radar Reflection (WARR) configuration. Comparison of results measured with reflected waves and direct waves was of main importance since they have different behavior in relation with moisture variation, due to different path of propagation. This research activity has been carried out during one Short-Term Scientific Missions (STSM) funded by the COST (European Cooperation in Science and Technology) Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar" in November-December 2015. In context of durability evaluation of construction materials, several studies have been carried out by the I2M team, University of Bordeaux, using direct and reflected waves for the evaluation of water content on concrete and wood materials [1-3]. As related to the wood material there is one study carried out using the reflected waves on wood for different humidity and different wood samples, in all the direction of polarization using GPR technique ground coupled antenna at 1.5 GHz [3]. This work continued with different moisture content in order to study the behavior of direct waves as function of moisture. Results taken from those measurements are compared with them from Fixed Offset (reflected method) with one antenna (1.5GHz or 2.6GHz), realized from the previous studies from the I2M and already published [1-3]. The results taken from this work from the reflected waves, show that the effect of wood anisotropy is significant on the variation of relative permittivity with moisture content on wood sample and that is in good agreement with the previous results [3-6]. As related to the direct waves, a small

  18. Subcellular Electrical Measurements as a Function of Wood Moisture Content

    Science.gov (United States)

    Samuel L. Zelinka; José L. Colon Quintana; Samuel V. Glass; Joseph E. Jakes; Alex C. Wiedenhoeft

    2015-01-01

    The percolation model developed by Zelinka et al. was based upon macroscale measurements of the electrical conductivity and implicitly treats the wood material as homogenous. The transport mechanism proposed by Jakes et al. depends upon a moisture induced glass transition occurring in the hemicelluloses. This theory suggests that there are likely differences in the...

  19. Experimental Investigation of Moisture Driven Fracture in Solid Wood

    DEFF Research Database (Denmark)

    Larsen, Finn; Ormarsson, Sigurdur; Olesen, John Forbes

    2010-01-01

    Solid timber products, containing both heartwood and sapwood, often have a high tendency to crack during the drying process. This can cause severe loss of material for the saw-mills, especially for products with large cross sectional dimensions. The cracks (e.g. end-cracks) arise, in some cases......, early in the drying process and close again later in the process. It can be difficult to see the closed cracks with visual grading. This may result in too high grading of the damaged material which may cause problems for customers such as building and furniture industries. Moisture content (MC) in green...... wood varies within the cross section of a timber log. The MC of heartwood, for example, is considerable lower than the MC of sapwood. Shrinkage starts at different times within different parts of the cross section, which results in a complex state of strains and stresses. The moisture related crack...

  20. Moisture Content Monitoring of a Timber Footbridge

    Directory of Open Access Journals (Sweden)

    Niclas Björngrim

    2016-03-01

    Full Text Available Construction of modern timber bridges has greatly increased during the last 20 years in Sweden. Wood as a construction material has several advantageous properties, e.g., it is renewable, sustainable, and aesthetically pleasing, but it is also susceptible to deterioration. To protect wood from deterioration and ensure the service life, the wood is either treated or somehow covered. This work evaluates a technology to monitor the moisture content in wood constructions. Monitoring the moisture content is important both to verify the constructive protection and for finding areas with elevated levels of moisture which might lead to a microbiological attack of the wood. In this work, a timber bridge was studied. The structure was equipped with six wireless sensors that measured the moisture content of the wood and the relative humidity every hour. Data for 744 days of the bridge are presented in this paper. Results show that the technology used to monitor the bridge generally works; however, there were issues due to communication problems and malfunction of sensors. This technology is promising for monitoring the state of wood constructions, but a more reliable sensor technology is warranted continuous remote monitoring of wood bridges over long periods of time.

  1. Measurement of Moisture in Wood for Application in the Restoration of Old Buildings.

    Science.gov (United States)

    Moron, Carlos; Garcia-Fuentevilla, Luisa; Garcia, Alfonso; Moron, Alberto

    2016-05-14

    There are many historic buildings whose construction is based on timber frame walls. Most buildings built during the nineteenth and early twentieth centuries were based on timber frame walls with vertical support elements. These timber frame elements are affected by their moisture content and by the passage of time. If the interaction of the timber frame walls with hygrothermal fluctuations were known, the maintenance of these buildings could be improved significantly. To determine the moisture content of wood there are two types of meters on the market: on the one hand, capacitance meters which consist of two side ends and where the moisture content is measured locally between two peaks. On the other hand, there are meters based on the variation of electromagnetic transmittance of timber, which depends on the moisture of timber. The second ones are very expensive and difficult to handle. This work presents a new non-intrusive capacitive sensor that measures the global moisture content in a section of the timber frame walls and therefore its accuracy is similar to the accuracy that can be obtained with electromagnetic transmittance meters. Additionally, as it is a capacitive sensor, it is low cost and easy to operate.

  2. Thermal/moisture-related stresses and fracture behaviour in solid wood members during forced drying

    DEFF Research Database (Denmark)

    Larsen, Finn

    , in particular the stress and cracking that takeplace during kiln-drying. Both experimental and numerical work was carried out so as to obtain knowledge regarding stress, strain, mechano-sorption and crackbehaviours in wood during drying.The investigations aimed also at revealing how drying damagecan best...... of wood without injury to the timber itself. When solid wood products are dried from a green condition down to an average moisture content level close to the service life conditions of the final product, significant moisture-induced stresses and related fracturing can occur. The drying stresses arise...... with a drying history that was generated, to verify a model that was used to simulate disc samples of the same type. The stresses were analyzed so as to clarify whether and when critical stress stateswere encountered during the drying process. The reversibility of the mechano-sorptive strains, i...

  3. ASSESSMENT OF THE MOISTURE EFFECT ON GASEOUS PRODUCTS OF SELF-HEATING OF WOOD CHIPS

    Directory of Open Access Journals (Sweden)

    Hana VĚŽNÍKOVÁ

    2017-12-01

    Full Text Available Biofuels are stored in large quantities and may be susceptible to self-ignition. The possible methods of indication of temperature increase include the analysis of the gaseous products of heating where concentrations of certain gases may increase with increasing temperature. Gas release is also affected by the moisture of the material given that the moisture level changes surface accessibility for oxygen on the one side and serves as a catalyst of the oxidation reactions on the other. The present project analysed the effect of temperature and moisture on gaseous products of heating of wood chips, one of frequently used biofuels, with the aim to determine a suitable gaseous indicator of beginning self-ignition.

  4. DETERMINATION OF MOISTURE DIFFUSION COEFFICIENT OF LARCH BOARD WITH FINITE DIFFERENCE METHOD

    Directory of Open Access Journals (Sweden)

    Qiaofang Zhou

    2011-04-01

    Full Text Available This paper deals with the moisture diffusion coefficient of Dahurian Larch (Larix gmelinii Rupr. by use of the Finite Difference Method (FDM. To obtain moisture distributions the dimensional boards of Dahurian Larch were dried, from which test samples were cut and sliced evenly into 9 pieces in different drying periods, so that moisture distributions at different locations and times across the thickness of Dahurian Larch were obtained with a weighing method. With these experimental data, FDM was used to solve Fick’s one-dimensional unsteady-state diffusion equation, and the moisture diffusion coefficient across the thickness at specified time was obtained. Results indicated that the moisture diffusion coefficient decreased from the surface to the center of the Dahurian Larch wood, and it decreased with decreasing moisture content at constant wood temperature; as the wood temperature increased, the moisture diffusion coefficient increased, and the effect of the wood temperature on the moisture diffusion coefficient was more significant than that of moisture content. Moisture diffusion coefficients were different for the two experiments due to differing diffusivity of the specimens.

  5. Measurement of Moisture in Wood for Application in the Restoration of Old Buildings

    Science.gov (United States)

    Moron, Carlos; Garcia-Fuentevilla, Luisa; Garcia, Alfonso; Moron, Alberto

    2016-01-01

    There are many historic buildings whose construction is based on timber frame walls. Most buildings built during the nineteenth and early twentieth centuries were based on timber frame walls with vertical support elements. These timber frame elements are affected by their moisture content and by the passage of time. If the interaction of the timber frame walls with hygrothermal fluctuations were known, the maintenance of these buildings could be improved significantly. To determine the moisture content of wood there are two types of meters on the market: on the one hand, capacitance meters which consist of two side ends and where the moisture content is measured locally between two peaks. On the other hand, there are meters based on the variation of electromagnetic transmittance of timber, which depends on the moisture of timber. The second ones are very expensive and difficult to handle. This work presents a new non-intrusive capacitive sensor that measures the global moisture content in a section of the timber frame walls and therefore its accuracy is similar to the accuracy that can be obtained with electromagnetic transmittance meters. Additionally, as it is a capacitive sensor, it is low cost and easy to operate. PMID:27187410

  6. Variation in seasonal moisture content

    Science.gov (United States)

    John E. Phelps

    1992-01-01

    Several properties of wood are affected by moisture content-weight, fuel value, electrical conductivity, strength, and shrinkage. Differences in these properties are commonly observed in wood in service. For example, a green 2 X 4 weighs more than a kiln-dried 2 X 4, dried wood burns more easily and hotter than green wood, etc.

  7. Influence of wood moisture content on the modulus of elasticity in compression parallel to the grain

    Directory of Open Access Journals (Sweden)

    Diogo Aparecido Lopes Silva

    2012-04-01

    Full Text Available Brazilian Standard ABNT NBR7190:1997 for timber structures design, adopts a first degree equation to describe the influence of wood moisture content. Periodically, when necessary, the referred standard is revised in order to analyze inconsistencies and to adopt considerations according new realities verified. So, the present paper aims to examine the adequacy of its equation which corrects to 12% of moisture the values of rigidity properties obtained on experimental tests. To quantify the moisture influence on modulus of elasticity, it was applied tests of compression parallel to the grain for six specimens of different strength classes, considering nominal moisture of 12; 20; 25; 30%. As results, modulus of elasticity in the moisture range 25-30% showed statistically equivalents, and was obtained a first degree equation to correlate the studied variables which leads to statically equivalent estimations when compared with results by ABNT NBR7190:1997 equation. However, it was indicated to maintain the current expression for the next text of the referred document review, without prejudice to statistical significance of the estimates.

  8. Effects of Exterior Insulation on Moisture Performance of Wood-Frame Walls in the Pacific Northwest: Measurements and Hygrothermal Modeling

    Science.gov (United States)

    Samuel V. Glass; Borjen Yeh; Benjamin J. Herzog

    2016-01-01

    Continuous exterior insulation on above-grade walls is becoming more common in many parts of North America. It is generally accepted that exterior insulation provides advantages for energy performance, by reducing thermal bridging, and for moisture performance, by warming the wood structural members, thereby reducing the potential for wintertime moisture accumulation....

  9. Moisture Conditions in Passive House Wall Constructions

    OpenAIRE

    Gullbrekken, Lars; Geving, Stig; Time, Berit; Andresen, Inger

    2015-01-01

    Buildings for the future, i.e zero emission buildings and passive houses, will need well insulated building envelopes, which includes increased insulation thicknesses for roof, wall and floor constructions. Increased insulation thicknesses may cause an increase in moisture levels and thereby increased risk of mold growth. There is need for increased knowledge about moisture levels in wood constructions of well insulated houses, to ensure robust and moisture safe solutions. Monitoring of w...

  10. Implementation of sorption hysteresis in multi-Fickian moisture transport

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lund; Svensson, Staffan

    2007-01-01

    In the cellular structure of wood, bound-water diffusion and water-vapor diffusion interact via sorption in a complex moisture-transportation system. At low relative humidities, moisture transport may be modeled by a Fickian diffusion equation with a good approximation. At higher relative......-35% in moisture content. Hence, for a precise moisture content computation, sorption hysteresis must be taken into account. The present paper explains the relation between sorption hysteresis and multi-Fickian moisture transport, and clarifies how models for the two phenomena are coupled. To illustrate...

  11. Fastener Corrosion: A Result of Moisture Problems in the Building Envelope

    Science.gov (United States)

    Samuel L. Zelinka

    2013-01-01

    This paper reviews recent literature on the corrosion of metals embedded in wood and highlights the link be-tween moisture accumulation in wood and fastener cor-rosion. Mechanisms of fastener corrosion are described including dependence upon wood moisture content. These fundamental concepts are applied to practical examples by explaining how hygrothermal models can be...

  12. Analysis of Joint Masonry Moisture Content Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Kohta [Building Science Corporation, Westford, MA (United States)

    2015-10-01

    Adding insulation to the interior side of walls of masonry buildings in cold (and wet) climates may cause performance and durability problems. Some concerns, such as condensation and freeze-thaw, have known solutions, but wood members embedded in the masonry structure will be colder (and potentially wetter) after an interior insulation retrofit. Moisture content & relative humidity were monitored at joist ends in historic mass brick masonry walls retrofitted with interior insulation in a cold climate (Zone 5A); data were collected from 2012-2015. Eleven joist ends were monitored in all four orientations. One limitation of these results is that the renovation is still ongoing, with limited wintertime construction heating and no permanent occupancy to date. Measurements show that many joists ends remain at high moisture contents, especially at north- and east-facing orientations, with constant 100% RH conditions at the worst cases. These high moisture levels are not conducive for wood durability, but no evidence for actual structural damage has been observed. Insulated versus non-insulated joist pockets do not show large differences. South facing joists have safe (10-15%) moisture contents. Given the uncertainty pointed out by research, definitive guidance on the vulnerability of embedded wood members is difficult to formulate. In high-risk situations, or when a very conservative approach is warranted, the embedded wood member condition can be eliminated entirely, supporting the joist ends outside of the masonry pocket.

  13. Edge effects on moisture reduce wood decomposition rate in a temperate forest.

    Science.gov (United States)

    Crockatt, Martha E; Bebber, Daniel P

    2015-02-01

    Forests around the world are increasingly fragmented, and edge effects on forest microclimates have the potential to affect ecosystem functions such as carbon and nutrient cycling. Edges tend to be drier and warmer due to the effects of insolation, wind, and evapotranspiration and these gradients can penetrate hundreds of metres into the forest. Litter decomposition is a key component of the carbon cycle, which is largely controlled by saprotrophic fungi that respond to variation in temperature and moisture. However, the impact of forest fragmentation on litter decay is poorly understood. Here, we investigate edge effects on the decay of wood in a temperate forest using an experimental approach, whereby mass loss in wood blocks placed along 100 m transects from the forest edge to core was monitored over 2 years. Decomposition rate increased with distance from the edge, and was correlated with increasing humidity and moisture content of the decaying wood, such that the decay constant at 100 m was nearly twice that at the edge. Mean air temperature decreased slightly with distance from the edge. The variation in decay constant due to edge effects was larger than that expected from any reasonable estimates of climatic variation, based on a published regional model. We modelled the influence of edge effects on the decay constant at the landscape scale using functions for forest area within different distances from edge across the UK. We found that taking edge effects into account would decrease the decay rate by nearly one quarter, compared with estimates that assumed no edge effect. © 2014 John Wiley & Sons Ltd.

  14. Analysis of Joist Masonry Moisture Content Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Kohta [Building Science Corporation, Westford, MA (United States)

    2015-10-08

    There are many existing buildings with load-bearing mass masonry walls, whose energy performance could be improved with the retrofit of insulation. However, adding insulation to the interior side of walls of such masonry buildings in cold (and wet) climates may cause performance and durability problems. Some concerns, such as condensation and freeze-thaw have known solutions. But wood members embedded in the masonry structure will be colder (and potentially wetter) after an interior insulation retrofit. Moisture content & relative humidity were monitored at joist ends in historic mass brick masonry walls retrofitted with interior insulation in a cold climate (Zone 5A); data were collected from 2012-2015. Eleven joist ends were monitored in all four orientations. One limitation of these results is that the renovation is still ongoing, with limited wintertime construction heating and no permanent occupancy to date. Measurements show that many joists ends remain at high moisture contents, especially at north- and east-facing orientations, with constant 100% RH conditions at the worst cases. These high moisture levels are not conducive for wood durability, but no evidence for actual structural damage has been observed. Insulated vs. non-insulated joist pockets do not show large differences. South facing joists have safe (10-15%) moisture contents. Given the uncertainty pointed out by research, definitive guidance on the vulnerability of embedded wood members is difficult to formulate. In high-risk situations, or when a very conservative approach is warranted, the embedded wood member condition can be eliminated entirely, supporting the joist ends outside of the masonry pocket.

  15. Moisture imaging of a camphor tree by neutron beam

    International Nuclear Information System (INIS)

    Nakanishi, Tomoko M.; Karakama, Isamu; Sakura, Tsuguo; Matsubayashi, Masashi

    1998-01-01

    Moisture distribution of a camphor tree was presented. A 23 year old camphor tree was downed at university forest and a wood disk, about 1 cm in width, was lumbered out from the breast height of the tree. The wood disk as well as a newly developing branch of the tree were irradiated with thermal neutrons at an atomic reactor installed at Japan Atomic Energy Research Institute. The total flux of thermal neutron was 3.0 x 10 9 n/cm 2 . Water specific images of the disk and a branch were presented with high resolution, which was estimated to be about 16 μm. In the case of wood disk, moisture decreasing manner while drying was also shown through neutron image. Neutron images showed that the moisture decreasing rate in sapwood was similar to that of heartwood. (author)

  16. Electromagnetic characterization of white spruce at different moisture contents using synthetic aperture radar imaging

    Science.gov (United States)

    Ingemi, Christopher M.; Owusu Twumasi, Jones; Yu, Tzuyang

    2018-03-01

    Detection and quantification of moisture content inside wood (timber) is key to ensuring safety and reliability of timber structures. Moisture inside wood attracts insects and fosters the development of fungi to attack the timber, causing significant damages and reducing the load bearing capacity during their design life. The use of non-destructive evaluation (NDE) techniques (e.g., microwave/radar, ultrasonic, stress wave, and X-ray) for condition assessment of timber structures is a good choice. NDE techniques provide information about the level of deterioration and material properties of timber structures without obstructing their functionality. In this study, microwave/radar NDE technique was selected for the characterization of wood at different moisture contents. A 12 in-by-3.5 in-by-1.5 in. white spruce specimen (picea glauca) was imaged at different moisture contents using a 10 GHz synthetic aperture radar (SAR) sensor inside an anechoic chamber. The presence of moisture was found to increase the SAR image amplitude as expected. Additionally, integrated SAR amplitude was found beneficial in modeling the moisture content inside the wood specimen.

  17. Evaluation of wood structure using GPR with FO method - Effect of moisture, fibers direction and density

    Science.gov (United States)

    Chinh Maï, Tien; Reci, Hamza; Sbartaï, Zoubir Mehdi; Pajewski, Lara; Marciniak, Marian

    2017-04-01

    This work deals with the potential of GPR method in the evaluation of wood structure in relation with density of wood (different wood species), the orientation of fibers and water content (Maï et al., 2015; Reci et al., 2016). The system of measurements is the georadar type (GPR-ground penetrating radar) composed of an electromagnetic signal generator (SIR 3000 of GSSI), and one couple of antennas, one Transmitter (T) and a Receiver (R) of 1.5GHz center frequency, located in the same box in a fixed distance of 6cm. Six wood samples are tested, three samples of Epicea and three samples of Pine. To compare and analyze the results of dielectric constants, we have used the data on three principal directions (Transvesal, Longitudinal and Radial). We note that the dielectric constant of wood increases with the moisture by mass as a consequence of increasing polarization and the conduction phenomena. This effect is more distinguished when the electric field is polarized parallel to the fibers than in perpendicular direction. The smallest contrasts are observed in the radial direction. We conclude that is more appropriate to evaluate the water content along the parallel direction of fibers. In this case we observe the maximum of contrasts of dielectric contrasts between dry and humidity states. Differences on dielectric constant, spectras and amplitudes are taken between different wood samples. Knowing that the dielectric constant is related to the capacity of polarizing (dependent on the water quantity), the increasing of water content could explain the difference of values obtained for the dielectric constants between two kinds of wood. Acknowledgement The Authors are grateful to COST - European Cooperation in Science and Technology (www.cost.eu) for funding the Action TU1208 "Civil engineering applications of Ground Penetrating Radar" (www.GPRadar.eu). We acknowledge also the French National Research Agency (ANR) for supporting this study through the Xylo-plate project

  18. The effect of changing ambient humidity on moisture condition in timber elements

    DEFF Research Database (Denmark)

    Hozjan, Tomaẑ; Turk, Goran; Srpĉiĉ, Stanislav

    2012-01-01

    a fully coupled transport model including a model for the influential sorption hysteresis of wood is used. The coupled model accounts for both vapor transport in pores and bound water transport in wood tissue. Moisture state history influences relationship between moisture state of wood and air humidity......This paper deals with the effect of the changing ambient humidity on moisture conditions in timber elements. The naturally varying humidity is possible to model as a relative combination of different harmonic cycles, with different periods and amplitudes. For the determination of the moisture field......, it must therefore be taken into account. In order to include history dependency, a hysteresis model is used here. Results from numerical calculations for timber specimen exposed to combined daily and annually cyclic variation of outside humidity are presented. Copyright © (2012) by WCTE 2012 Committee....

  19. Using a quasi-heat-pulse method to determine heat and moisture transfer properties for porous orthotropic wood products or cellular solid materials

    Science.gov (United States)

    M. A. Dietenberger

    2006-01-01

    Understanding heat and moisture transfer in a wood specimen as used in the K-tester has led to an unconventional numerical solution arid intriguing protocol to deriving the transfer properties. Laplace transform solutions of Luikov’s differential equations are derived for one-dimensional heat and moisture transfer in porous hygroscopic orthotropic materials and for a...

  20. Non-destructive determination of moisture content and micro-fibril angle of wood using a poly-chromatic X-ray beam theoretical and experimental approach

    International Nuclear Information System (INIS)

    Baettig, R.

    2005-07-01

    Non-destructive determination of moisture content and micro-fibril angle are important stakes for the sciences of the wood because these two parameters influence strongly the macroscopic behavior of the wood. For example, the shrinkage, the mechanical properties, the thermal and acoustic conductivity are dependent on the moisture content and their anisotropic character is largely governed by the micro-fibril angle. We used the light difference between X-ray mass attenuation coefficient for the water and for the wood in transmission. Regrettably, the results show that this difference between X-ray mass attenuation coefficient is insufficient to allow the precise measurement of the moisture content.In spite of this, the coherent scattering shows sensitive effects. So, by using a poly-energetic beam and a spectrometric system, we were able to discriminate between the crystalline constituent (cellulose) of the amorphous constituent (water) in a sample of wet wood, because for a given angle these phases scatter in different energy. Besides, the device created allowed us to study the crystalline phase of the wood. We were able to confront experimental profiles of diffraction with theoretical profiles of diffraction, obtained by means of a rigorous simulation, in the objective to estimate the average micro-fibril angle and its standard deviation. (author)

  1. Dependence of Microcrack Behavior in Wood on Moisture Content during Drying

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yamamoto

    2013-01-01

    Full Text Available A modified confocal laser scanning microscopy (CLSM system was developed not only to observe the microcracks on the surface of Cryptomeria japonica D. Don in situ at the cellular level but also to obtain information about the moisture content (MC of the wood surface by measuring the change in its electrical resistivity. The sequential images and changes in the electrical resistivity of the wood surface indicated that microcracks formed between the tracheid and ray parenchyma in the latewood region at >1.0E + 07 Ω/sq (square. Microcracks formed when the MC of the wood surface was below the fiber saturation point determined through regression analysis of the surface electrical resistivity and MC. Most of the microcracks develop when the surface electrical resistivity ranged from 3.95E + 10 to 3.60E + 12 Ω/sq. When the surface MC was ~2.5%, microcracks closed and the surface electrical resistivity was either ~1.00E + 15 Ω/sq or outside the measurement range. The modified CLSM and the method to measure the MC of the wood surface can be used to acquire information about the surface MC in specific areas shown in CLSM images. The findings indicated that the MC of the surface of the wood plays an important role in suppressing the emergence of microcracks in drying wood. The modified CLSM system and the method of measuring the MC of the surface of wood can be used to efficiently evaluate methods of drying wood and the quality of dried wood.

  2. Umidade de equilíbrio de painéis de madeira Equilibrium moisture content of wood panels

    Directory of Open Access Journals (Sweden)

    Graciane Angélica da Silva

    2005-08-01

    Full Text Available Este estudo teve como objetivo a determinação da umidade de equilíbrio de painéis de madeira numa câmara de climatização e comparação dos seus valores com os obtidos através da equação de Nelson. O trabalho foi desenvolvido na Unidade Experimental de Produção de Painéis de Madeira da Universidade Federal de Lavras. Foram utilizadas amostras de aglomerado, compensado multilaminado e sarrafeado, chapa dura, OSB (Oriented Strand Board , MDF (Medium Density Fiberboard, HDF (High Density Fiberboard, madeira-cimento e madeira-pl��stico, sendo esses produtos de escala industrial e experimental. As dimensões dos corpos-de-prova foram de 2,60 cm de largura por 2,60 cm de comprimento. As espessuras foram aquelas mais utilizadas comercialmente de cada produto, sendo utilizadas cinco repetições por painel. Os corpos-de-prova foram pesados e levados para uma câmara de climatização, onde foram submetidos a diferentes condições de umidade relativa (90, 80, 70, 60, 50 e 40% e uma temperatura constante de 30 ºC. Determinaram-se a histerese e a umidade de equilíbrio, que variaram de 40 a 90%. Os resultados indicaram que a equação de Nelson se mostrou eficiente na estimativa da umidade de equilíbrio e que não existe em média diferença de histerese entre os produtos estudados, mostrando que todos apresentam a mesma estabilidade dimensional. Observou-se, também, que o revestimento dos painéis não afetou a umidade de equilíbrio.This study aimed at determining the equilibrium moisture content of wood panels in a climatization chamber and comparing the values of equilibrium moisture content found with those given by Nelson's equation. The research was developed at the Experimental Unit of Wood Panel Production of the Universidade Federal de Lavras. Samples of particleboard, plywood, hardboard, OSB (Oriented Strand Board, MDF (Medium Density Fiberboard, HDF (High Density Fiberboard, cement wood and plastic wood were taken both from

  3. High-R Walls for Remodeling: Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J.; Kochkin, V.

    2012-12-01

    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  4. High-R Walls for Remodeling. Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Kochkin, V. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States)

    2012-12-01

    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  5. Measurement of log moisture content and density by gamma and neutron backscatter

    International Nuclear Information System (INIS)

    Barry, B.J.

    2002-01-01

    Measurement of the moisture content and green density of wood was investigated using scattering of gamma rays and neutrons. Both of these processes are dependent on density but neutrons are particularly sensitive to the hydrogen content, which changes with moisture content. A material mimicking the green density and moisture content of real wood was successfully used in a laboratory study to establish the feasibility of measuring these within the range found in standing trees. A later field trial indicated that the technique needed more development to take account of the natural variability of real trees. (author). 3 refs., 11 figs., 1 table

  6. Effect of cladding systems on moisture performance of wood-framed walls in a mixed-humid climate

    Science.gov (United States)

    S. Craig Drumheller; Charles G. Carll

    2010-01-01

    A 22-month field investigation of nine different north-and south-oriented wood-framed wall assemblies was conducted to determine the moisture performance of various wall construction types, most of which incorporated absorptive cladding. The study was conducted on the campus of the National Association of Home Builders (NAHB) Research Center, in Upper Marlboro, MD, 20...

  7. Design of a small scale boiler package for testing high moisture content biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Proctor, Andrew

    2005-07-01

    This report presents the results of a project to design a prototype, small-scale boiler (0.88 MWth output) to enable clean and efficient combustion of high moisture content (>30%) biomass fuels. The boiler was based on an open bottom smoke tube design, modified to incorporate water tubes in the combustion chamber running from front to back. These were added to support refractory bricks to create an extra pass in the boiler combustion chamber such that the reflected heat from the refractory increased the rate of evaporation of moisture from the fuel. A chain grate stoker was employed. The combustion tests involved three biofuels: wood pellets with a low moisture content (8-10%) (to provide combustion rates for a commercially proven biofuel); wood chips from forestry waste with a 30-40% moisture content; and spent mushroom compost with 70-75% moisture. The tests on the wood chips required a number of modifications to the fuel feeding system and to the boiler in order to achieve limited success and the tests with the mushroom compost were unsuccessful due to the combination of the high moisture content and the fuel's low calorific value. Experience gained with the wood chips suggested a number of improvements for a future boiler design. As well as describing the experimental work and test results, the report offers an economic analysis (capital costs, fuel costs, running costs) of the scheme.

  8. Moisture assessment by fast and non-destructive in situ measurements

    DEFF Research Database (Denmark)

    Hansen, Kurt Kielsgaard; Møller, Eva B.; Hansen, Ernst Jan de Place

    2014-01-01

    moisture content, which is not revealed by this inspection. The moisture content may become a problem for the buyers. This problem might have been avoided if the moisture content of the Building materials was measured on inspection. This is easily done in wood-based materials but for example in concrete...... to use, easily applicable and suitable for most porous building materials. Furthermore, the measurements must be reliable at the high end of the hygroscopic area and describe absolute moisture content or corresponding relative humidity. The existing methods for moisture measuring cannot meet...... on measurements of the relative humidity of the air in a small hood placed tightly and sealed to the surface of the construction. Results with aerated concrete covered with acrylic paint are presented....

  9. Photostability and moisture uptake properties of wood veneers coated with a combination of thin sol-gel films and light stabilizers

    Science.gov (United States)

    Mandla A. Tshabalala; Ryan Libert; Christian M. Schaller

    2011-01-01

    In recent years, there has been increased interest in the use of inorganic UV blocking nanoparticles for photostabilization of wood surfaces. Photostability and moisture uptake properties of wood veneers coated with a combination of hybrid inorganic-organic thin sol-gel films and organic light stabilizers was investigated. The light stabilizers were applied by brushing...

  10. Moisture Management for High R-Value Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lepage, R.; Schumacher, C.; Lukachko, A.

    2013-11-01

    The following report explains the moisture-related concerns for High R-value wall assemblies and discusses past Building America research work that informs this study. Hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones (2, 3, 4C, 4, 5A, and 7, respectively). The simulations are informed by experience gained from past research in this area and validated by field measurement and forensic experience. The modeling program was developed to assess the moisture durability of the wall assemblies based on three primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage. The peak annual moisture content of the wood based exterior sheathing was used to comparatively analyze the response to the moisture loads for each of the walls in each given city. Walls which experienced sheathing moisture contents between 20% and 28% were identified as risky, whereas those exceeding 28% were identified as very high risk. All of the wall assemblies perform well under idealized conditions. However, only the walls with exterior insulation, or cavity insulation which provides a hygrothermal function similar to exterior insulation, perform adequately when exposed to moisture loads. Walls with only cavity insulation are particularly susceptible to air leakage condensation. None of the walls performed well when a precipitation based bulk water leak was introduced to the backside of the sheathing, emphasizing the importance of proper flashing details.

  11. Moisture dependent of some physical and morphological properties ...

    African Journals Online (AJOL)

    The static coefficients for friction of dent corn seeds were determined steel, plywood, wood, glass and galvanized sheet at various moisture contents. The highest static coefficient of friction was found on the wood and the lowest on the glass sheet among the materials tested. Key words: Dent corn, physical properties, ...

  12. Equilibrium moisture content of OSB panels made from Eucalyptus urophylla clones

    Directory of Open Access Journals (Sweden)

    Lourival Marin Mendes

    2014-12-01

    Full Text Available This work aimed to verify the efficiency of Nelson's equation to estimate equilibrium moisture content of this material and provide a model for determination of moisture content of panels based on air relative moisture content, as well as to evaluate the effect of some processing variables on the equilibrium moisture content of OSB (Oriented Strand Board panels. The 25 x 25 mm samples were put in an acclimation room where they were kept at 30ºC and had their mass determined after stabilization at the relative air moisture contents of 40, 50, 60, 70, 80 and 90%. By the results obtained it was possible to conclude that: Nelson's equation tended to underestimate moisture values of the panel; the polynomial model adjusted based on the relative moisture of the air presented great potential to be used; although different behavior may be observed for the isotherms of treatments, there was no significant effect of the variables panel density, wood basic density, mat type and pressure temperature on mean equilibrium moisture content in desorption 1, adsorption and desorption 2.

  13. Measurements of moisture content in wood fuels with dual energy x-ray; Maetning av fukt i biobraenslen med dubbelenergiroentgen

    Energy Technology Data Exchange (ETDEWEB)

    Nordell, Anders [Industriellt Utvecklingscentrum i Karlskoga, Karlskoga (Sweden); Vikterloef, K J [Oerebro Radiofysik AB, Oerebro (Sweden)

    2000-04-01

    Good methods enabling quick determination of moisture in wood fuels are lacking. A standardized method generally used by the biofuel industry means drying samples in furnaces during at least 16 hours. The idea of this work has been to investigate if x-ray technique can offer a superior alternative for fast moisture determination. Analysis with x-ray has many advantages. The x-rays go completely through the whole test specimen. Large samples or many sequential samples can rapidly be measured. The penetration is extraordinary good; all parts of the tested mass will be analyzed. The measurement relies on the absorption of gamma photons in the tested mass. The x-ray absorption is carried out deep down in the atoms and therefore is independent of the materials equation of state as temperature, grain size or molecule binding. The disadvantages of the method are the general anxiety which can be for gamma rays, the relative high cost for equipment and the fact that an x-ray tube will wear with time and needs replacement. The method used here for moisture measurement is known as dual energy x-ray. The test sample is simultaneously exposed to transmission of two separate x-ray energies. The two energies are absorbed differently by the sample. The ratio of the absorption in the two respective energies is calculated and from that conclusions on the composition of the material can be drawn. The equipment used in this test is a standard medical apparatus adapted for the study of human body composition. When instead used for measurements of moisture in wood material the discrimination signal is about half of that achieved in the normal medical case. Despite that, the signal has been good enough for giving satisfactory accuracy in the moisture estimation. A little more than sixty approved results are presented in the report comprehending ten different fuel types. The results are grouped into three main categories depending on fuel type, wood fuels, peat fuels and salix including

  14. The Effect of Moisture of the Raw Material on the Properties Briquettes for Energy Use

    Directory of Open Access Journals (Sweden)

    Milan Brožek

    2016-01-01

    Full Text Available At logging and at the subsequent wood and wood semi-products treatment the fine grained loose waste is arising, e.g. wood dust, saw dust, shavings, chips, bark etc. One of possibilities of its meaningful utilization is the briquetting technology, which product are briquettes determined for energetic utilization (combustion. This report contains the results of tests carried out with the aim to assess the influence of moisture on the briquettes final properties. For the tests the platan tree chips of four moisture levels, namely 5.7 %, 7.7 %, 15.7 % and 23.9 % were used. The basic physical-mechanical properties were the evaluation criteria. Following properties were determined: ash amount, gross calorific value, total moisture content, density, rupture force, length, diameter, weight and mechanical durability. From the results of carried out tests it follows that the best properties were reached at briquettes made from chips of moisture 7.7 %. At higher or lower moisture the briquettes properties were sharply failing (namely rupture force and density.

  15. Evaluation of standard methods for collecting and processing fuel moisture samples

    Science.gov (United States)

    Sally M. Haase; José Sánchez; David R. Weise

    2016-01-01

    A variety of techniques for collecting and processing samples to determine moisture content of wildland fuels in support of fire management activities were evaluated. The effects of using a chainsaw or handsaw to collect samples of largediameter wood, containers for storing and transporting collected samples, and quick-response ovens for estimating moisture content...

  16. Comparative measurements of heat and moisture transfer in different wood-based building elements; Vergleichende Untersuchungen zum Feuchte- und Waermeverhalten unterschiedlicher Holzbauelemente

    Energy Technology Data Exchange (ETDEWEB)

    Joscak, Matus; Sonderegger, Walter; Niemz, Peter [ETH Zuerich, Institut fuer Baustoffe, Arbeitsgruppe Holzphysik, Zuerich (Switzerland); Holm, Andreas; Krus, Martin; Grosskinsky, Theo; Lengsfeld, Kristin [Fraunhofer-Institut fuer Bauphysik, Valley (Germany); Grunewald, John; Plagge, Rudolf [Technische Universitaet Dresden, Institut fuer Bauklimatik, Dresden (Germany)

    2011-10-15

    At the campus of the Fraunhofer Institute for Building Physics (IBP) in Holzkirchen/Germany comparative measurements of heat and moisture transfer in five different wood-based building elements were carried out (wood construction with slotted wood elements, solid wood construction connected with wooden dowels, new developed soft fibreboard brick construction, solid wood panel construction, wood frame construction with stacked wood elements). The elements were installed on the west side of the test building and examined during one year. The following physical quantities were measured: indoor climate, external and internal surface temperatures, temperatures in the boundary layers, heat flux through the internal surface of the constructions, relative humidity and moisture content. Furthermore, the measured data were used for validation of the simulation softwares WUFI {sup registered} Pro and Delphin. During winter, the measured U-values (from unsteady-state values) were compared with steady-state calculated U-values. Both values were well coincident. Moreover, the simulation results achieved good agreement by using the thermal conductivity values measured at ETH Zurich, which were considerably lower than the standard values. Although, the four elements had been covered with a non rear-ventilated facade, no critical values of relative humidity were measured inside the constructions. The simulation results of relative humidity have partly shown large deviations from measured data by both simulation softwares.

  17. Moisture conditions in buildings

    DEFF Research Database (Denmark)

    Rode, Carsten

    2012-01-01

    Growth of mould requires the presence of moisture at a certain high level. In a heated indoor environment such moisture levels occur only if there is a reason for the moisture supply. Such moisture can come from the use of the building, because of malfunctioning constructions, or it can be the re......Growth of mould requires the presence of moisture at a certain high level. In a heated indoor environment such moisture levels occur only if there is a reason for the moisture supply. Such moisture can come from the use of the building, because of malfunctioning constructions, or it can...

  18. Predicting moisture state of timber members in a continuously varying climate

    DEFF Research Database (Denmark)

    Svensson, Staffan; Turk, Goran; Hozjan, Tomaz

    2011-01-01

    A prerequisite for a sensible estimate of moisture induced stresses in timber members is an accurate prediction of the members’ moisture states during their service life. There are, however, an infinite number of possible moisture states for an arbitrary timber member in a natural varying climate...... the realizations were made, are based on a fully coupled transport model including a model for the influential sorption hysteresis of wood. A format containing required information suitable for assessing the “moisture” action on timber members is proposed. In addition it is illustrated how a model of high...

  19. Dendrochronological analysis of white oak growth patterns across a topographic moisture gradient in southern Ohio

    Science.gov (United States)

    Alexander K. Anning; Darrin L. Rubino; Elaine K. Sutherland; Brian C. McCarthy

    2013-01-01

    Moisture availability is a key factor that influences white oak (Quercus alba L.) growth and wood production. In unglaciated eastern North America, available soil moisture varies greatly along topographic and edaphic gradients. This study was aimed at determining the effects of soil moisture variability and macroclimate on white oak growth in mixed-oak forests of...

  20. Understanding natural moisturizing mechanisms: implications for moisturizer technology.

    Science.gov (United States)

    Chandar, Prem; Nole, Greg; Johnson, Anthony W

    2009-07-01

    Dry skin and moisturization are important topics because they impact the lives of many individuals. For most individuals, dry skin is not a notable concern and can be adequately managed with current moisturizing products. However, dry skin can affect the quality of life of some individuals because of the challenges of either harsh environmental conditions or impaired stratum corneum (SC) dry skin protection processes resulting from various common skin diseases. Dry skin protection processes of the SC, such as the development of natural moisturizing factor (NMF), are complex, carefully balanced, and easily perturbed. We discuss the importance of the filaggrin-NMF system and the composition of NMF in both healthy and dry skin, and also reveal new insights that suggest the properties required for a new generation of moisturizing technologies.

  1. Opto-thermal moisture content and moisture depth profile measurements in organic materials

    NARCIS (Netherlands)

    Xiao, P.; Guo, X.; Cui, Y.Y.; Imhof, R.; Bicanic, D.D.

    2004-01-01

    Opto-thermal transient emission radiometry(OTTER) is a infrared remote sensing technique, which has been successfully used in in vivo skin moisture content and skin moisture depth profiling measurements.In present paper, we extend this moisture content measurement capability to analyze the moisture

  2. Evaluation of Assimilated SMOS Soil Moisture Data for US Cropland Soil Moisture Monitoring

    Science.gov (United States)

    Yang, Zhengwei; Sherstha, Ranjay; Crow, Wade; Bolten, John; Mladenova, Iva; Yu, Genong; Di, Liping

    2016-01-01

    Remotely sensed soil moisture data can provide timely, objective and quantitative crop soil moisture information with broad geospatial coverage and sufficiently high resolution observations collected throughout the growing season. This paper evaluates the feasibility of using the assimilated ESA Soil Moisture Ocean Salinity (SMOS)Mission L-band passive microwave data for operational US cropland soil surface moisture monitoring. The assimilated SMOS soil moisture data are first categorized to match with the United States Department of Agriculture (USDA)National Agricultural Statistics Service (NASS) survey based weekly soil moisture observation data, which are ordinal. The categorized assimilated SMOS soil moisture data are compared with NASSs survey-based weekly soil moisture data for consistency and robustness using visual assessment and rank correlation. Preliminary results indicate that the assimilated SMOS soil moisture data highly co-vary with NASS field observations across a large geographic area. Therefore, SMOS data have great potential for US operational cropland soil moisture monitoring.

  3. Reducing the moisture effect on the creep deformation of wood by an irradiation-induced polymer impregnation method

    International Nuclear Information System (INIS)

    Chia, L.H.L.; Boey, F.Y.C.; Teoh, S.H.

    1988-01-01

    This paper reports an attempt to reduce the sensitivity of creep deformation to moisture adsorption by impregnating a tropical wood with methyl-methacrylate and subsequent polymerization by γ-irradiation. Beam specimens both of untreated wood and polymer impregnated wood were subjected to a three-point bend creep test under a constant load of 300 N at 23 ± 1 0 C, at three different humidity levels of 50 ± 5, 65 ± 5 and 85 ± 5%. A Norton-Bailey (power law) mathematical model successfully described the creep behaviour, with the creep components determined by a non-linear regression analysis. A significant reduction in the sensitivity of creep deformation to the humidity level was attained for the polymer impregnated wood. This could be explained by the ability of the impregnated polymer to form a strongly adhesive interface with the wood cell material, thereby acting as a physical barrier to reduce the movement of water to and from the wood cell material. (author)

  4. Sampling procedure in a willow plantation for estimation of moisture content

    DEFF Research Database (Denmark)

    Nielsen, Henrik Kofoed; Lærke, Poul Erik; Liu, Na

    2015-01-01

    Heating value and fuel quality of wood is closely connected to moisture content. In this work the variation of moisture content (MC) of short rotation coppice (SRC) willow shoots is described for five clones during one harvesting season. Subsequently an appropriate sampling procedure minimising...... labour costs and sampling uncertainty is proposed, where the MC of a single stem section with the length of 10–50 cm corresponds to the mean shoot moisture content (MSMC) with a bias of maximum 11 g kg−1. This bias can be reduced by selecting the stem section according to the particular clone...

  5. Investigation of Historic Equilibrium Moisture Content Data from the Forest Products Laboratory

    Science.gov (United States)

    Samuel V. Glass; Samuel L. Zelinka; Jay A. Johnson

    2014-01-01

    The Forest Products Laboratory (FPL) has provided equilibrium moisture content (EMC) values of wood for given temperature and relative humidity (RH) conditions in various forms over the course of its history, primarily for practical purposes related to drying lumber and controlling moisture content. The FPL EMC data have been widely cited and reprinted, not only in...

  6. Multiscale soil moisture estimates using static and roving cosmic-ray soil moisture sensors

    Science.gov (United States)

    McJannet, David; Hawdon, Aaron; Baker, Brett; Renzullo, Luigi; Searle, Ross

    2017-12-01

    Soil moisture plays a critical role in land surface processes and as such there has been a recent increase in the number and resolution of satellite soil moisture observations and the development of land surface process models with ever increasing resolution. Despite these developments, validation and calibration of these products has been limited because of a lack of observations on corresponding scales. A recently developed mobile soil moisture monitoring platform, known as the rover, offers opportunities to overcome this scale issue. This paper describes methods, results and testing of soil moisture estimates produced using rover surveys on a range of scales that are commensurate with model and satellite retrievals. Our investigation involved static cosmic-ray neutron sensors and rover surveys across both broad (36 × 36 km at 9 km resolution) and intensive (10 × 10 km at 1 km resolution) scales in a cropping district in the Mallee region of Victoria, Australia. We describe approaches for converting rover survey neutron counts to soil moisture and discuss the factors controlling soil moisture variability. We use independent gravimetric and modelled soil moisture estimates collected across both space and time to validate rover soil moisture products. Measurements revealed that temporal patterns in soil moisture were preserved through time and regression modelling approaches were utilised to produce time series of property-scale soil moisture which may also have applications in calibration and validation studies or local farm management. Intensive-scale rover surveys produced reliable soil moisture estimates at 1 km resolution while broad-scale surveys produced soil moisture estimates at 9 km resolution. We conclude that the multiscale soil moisture products produced in this study are well suited to future analysis of satellite soil moisture retrievals and finer-scale soil moisture models.

  7. Effect of moisture availability on wood density and vessel characteristics of Eucalyptus grandis in the warm temperate region of South Africa

    CSIR Research Space (South Africa)

    Naidoo, Sasha

    2006-09-01

    Full Text Available intolerant of adverse conditions, and performs poorly when planted on shallow soils and/or on dry sites. A study was conducted to assess the effect of moisture availability on the wood density and vessel characteristics of E. grandis grown in the warm...

  8. Validation of soil moisture ocean salinity (SMOS) satellite soil moisture products

    Science.gov (United States)

    The surface soil moisture state controls the partitioning of precipitation into infiltration and runoff. High-resolution observations of soil moisture will lead to improved flood forecasts, especially for intermediate to large watersheds where most flood damage occurs. Soil moisture is also key in d...

  9. A 3D moisture-stress FEM analysis for time dependent problems in timber structures

    Science.gov (United States)

    Fortino, Stefania; Mirianon, Florian; Toratti, Tomi

    2009-11-01

    This paper presents a 3D moisture-stress numerical analysis for timber structures under variable humidity and load conditions. An orthotropic viscoelastic-mechanosorptive material model is specialized on the basis of previous models. Both the constitutive model and the equations needed to describe the moisture flow across the structure are implemented into user subroutines of the Abaqus finite element code and a coupled moisture-stress analysis is performed for several types of mechanical loads and moisture changes. The presented computational approach is validated by analyzing some wood tests described in the literature and comparing the computational results with the reported experimental data.

  10. MoisturEC: a new R program for moisture content estimation from electrical conductivity data

    Science.gov (United States)

    Terry, Neil; Day-Lewis, Frederick D.; Werkema, Dale D.; Lane, John W.

    2018-01-01

    Noninvasive geophysical estimation of soil moisture has potential to improve understanding of flow in the unsaturated zone for problems involving agricultural management, aquifer recharge, and optimization of landfill design and operations. In principle, several geophysical techniques (e.g., electrical resistivity, electromagnetic induction, and nuclear magnetic resonance) offer insight into soil moisture, but data‐analysis tools are needed to “translate” geophysical results into estimates of soil moisture, consistent with (1) the uncertainty of this translation and (2) direct measurements of moisture. Although geostatistical frameworks exist for this purpose, straightforward and user‐friendly tools are required to fully capitalize on the potential of geophysical information for soil‐moisture estimation. Here, we present MoisturEC, a simple R program with a graphical user interface to convert measurements or images of electrical conductivity (EC) to soil moisture. Input includes EC values, point moisture estimates, and definition of either Archie parameters (based on experimental or literature values) or empirical data of moisture vs. EC. The program produces two‐ and three‐dimensional images of moisture based on available EC and direct measurements of moisture, interpolating between measurement locations using a Tikhonov regularization approach.

  11. On-line moisture analysis

    International Nuclear Information System (INIS)

    Cutmore, N.G.; Mijak, D.G

    2002-01-01

    Measurement of the moisture content of iron ore has become a key issue for controlling moisture additions for dust suppression. In most cases moisture content is still determined by manual or automatic sampling of the ore stream, followed by conventional laboratory analysis by oven drying. Although this procedure enables the moisture content to be routinely monitored, it is too slow for control purposes. This has generated renewed interest in on-line techniques for the accurate and rapid measurement of moisture in iron ore on conveyors. Microwave transmission techniques have emerged over the past 40 years as the dominant technology for on-line measurement of moisture in bulk materials, including iron ores. Alternative technologies have their limitations. Infra-red analysers are used in a variety of process industries, but rely on the measurement of absorption by moisture in a very thin surface layer. Consequently such probes may be compromised by particle size effects and biased presentation of the bulk material. Nuclear-based analysers measure the total hydrogen content in the sample and do not differentiate between free and combined moisture. Such analysers may also be sensitive to material presentation and elemental composition. Very low frequency electromagnetic probes, such as capacitance or conductance probes, operate in the frequency region where the DC conductivity dominates much of the response, which is a function not only of moisture content but also of ionic composition and chemistry. These problems are overcome using microwave transmission techniques, which also have the following advantages, as a true bulk moisture analysis is obtained, because a high percentage of the bulk material is analysed; the moisture estimate is mostly insensitive to any biased presentation of moisture, for example due to stratification of bulk material with different moisture content and because no physical contact is made between the sensor and the bulk material. This is

  12. MoisturEC: A New R Program for Moisture Content Estimation from Electrical Conductivity Data.

    Science.gov (United States)

    Terry, Neil; Day-Lewis, Frederick D; Werkema, Dale; Lane, John W

    2018-03-06

    Noninvasive geophysical estimation of soil moisture has potential to improve understanding of flow in the unsaturated zone for problems involving agricultural management, aquifer recharge, and optimization of landfill design and operations. In principle, several geophysical techniques (e.g., electrical resistivity, electromagnetic induction, and nuclear magnetic resonance) offer insight into soil moisture, but data-analysis tools are needed to "translate" geophysical results into estimates of soil moisture, consistent with (1) the uncertainty of this translation and (2) direct measurements of moisture. Although geostatistical frameworks exist for this purpose, straightforward and user-friendly tools are required to fully capitalize on the potential of geophysical information for soil-moisture estimation. Here, we present MoisturEC, a simple R program with a graphical user interface to convert measurements or images of electrical conductivity (EC) to soil moisture. Input includes EC values, point moisture estimates, and definition of either Archie parameters (based on experimental or literature values) or empirical data of moisture vs. EC. The program produces two- and three-dimensional images of moisture based on available EC and direct measurements of moisture, interpolating between measurement locations using a Tikhonov regularization approach. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

  13. On-line moisture analysis

    CERN Document Server

    Cutmore, N G

    2002-01-01

    Measurement of the moisture content of iron ore has become a key issue for controlling moisture additions for dust suppression. In most cases moisture content is still determined by manual or automatic sampling of the ore stream, followed by conventional laboratory analysis by oven drying. Although this procedure enables the moisture content to be routinely monitored, it is too slow for control purposes. This has generated renewed interest in on-line techniques for the accurate and rapid measurement of moisture in iron ore on conveyors. Microwave transmission techniques have emerged over the past 40 years as the dominant technology for on-line measurement of moisture in bulk materials, including iron ores. Alternative technologies have their limitations. Infra-red analysers are used in a variety of process industries, but rely on the measurement of absorption by moisture in a very thin surface layer. Consequently such probes may be compromised by particle size effects and biased presentation of the bulk mater...

  14. Increased profitability in cellulose production through more accurate measurement of the moisture content

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    A general report on the project 'Dry Wood' is presented. In this project Noratom-Norcontrol A/S cooperate with the wood-pulp and paper factory Petersen and Soen in the application of Noratom's radiometric moisture gauge and their continuous weighing machine (densimeter) in the continuous measurement of the moisture content of wood chips in cellulose production. Conventional methods give an accuracy of π+ 2% and the objective of this method is an accuracy of π+ 1%. This would have a considerable economic significance. A test unit has been operating in the production line for a year and has attained the objective for short periods. Improved long term stability is the present problem. The system has process outputs which will facilitate future on-line computer process control. (JIW)

  15. Analysis and optimal design of moisture sensor for rice grain moisture measurement

    Science.gov (United States)

    Jain, Sweety; Mishra, Pankaj Kumar; Thakare, Vandana Vikas

    2018-04-01

    The analysis and design of a microstrip sensor for accurate determination of moisture content (MC) in rice grains based on oven drying technique, this technique is easy, fast and less time-consuming to other techniques. The sensor is designed with low insertion loss, reflection coefficient and maximum gain is -35dB and 5.88dB at 2.68GHz as well as discussed all the parameters such as axial ratio, maximum gain, smith chart etc, which is helpful for analysis the moisture measurement. The variation in percentage of moisture measurement with magnitude and phase of transmission coefficient is investigated at selected frequencies. The microstrip moisture sensor consists of one layer: substrate FR4, thickness 1.638 is simulated by computer simulated technology microwave studio (CST MWS). It is concluded that the proposed sensor is suitable for development as a complete sensor and to estimate the optimum moisture content of rice grains with accurately, sensitivity, compact, versatile and suitable for determining the moisture content of other crops and agriculture products.

  16. MoisturEC: an R application for geostatistical estimation of moisture content from electrical conductivity data

    Science.gov (United States)

    Terry, N.; Day-Lewis, F. D.; Werkema, D. D.; Lane, J. W., Jr.

    2017-12-01

    Soil moisture is a critical parameter for agriculture, water supply, and management of landfills. Whereas direct data (as from TDR or soil moisture probes) provide localized point scale information, it is often more desirable to produce 2D and/or 3D estimates of soil moisture from noninvasive measurements. To this end, geophysical methods for indirectly assessing soil moisture have great potential, yet are limited in terms of quantitative interpretation due to uncertainty in petrophysical transformations and inherent limitations in resolution. Simple tools to produce soil moisture estimates from geophysical data are lacking. We present a new standalone program, MoisturEC, for estimating moisture content distributions from electrical conductivity data. The program uses an indicator kriging method within a geostatistical framework to incorporate hard data (as from moisture probes) and soft data (as from electrical resistivity imaging or electromagnetic induction) to produce estimates of moisture content and uncertainty. The program features data visualization and output options as well as a module for calibrating electrical conductivity with moisture content to improve estimates. The user-friendly program is written in R - a widely used, cross-platform, open source programming language that lends itself to further development and customization. We demonstrate use of the program with a numerical experiment as well as a controlled field irrigation experiment. Results produced from the combined geostatistical framework of MoisturEC show improved estimates of moisture content compared to those generated from individual datasets. This application provides a convenient and efficient means for integrating various data types and has broad utility to soil moisture monitoring in landfills, agriculture, and other problems.

  17. Moisture in Crawl Spaces

    Science.gov (United States)

    Anton TenWolde; Samuel V. Glass

    2013-01-01

    Crawl space foundations can be designed and built to avoid moisture problems. In this article we provide a brief overview of crawl spaces with emphasis on the physics of moisture. We review trends that have been observed in the research literature and summarize cur-rent recommendations for moisture control in crawl spaces.

  18. Buffer moisture protection system

    International Nuclear Information System (INIS)

    Ritola, J.; Peura, J.

    2013-11-01

    With the present knowledge, bentonite blocks have to be protected from the air relative humidity and from any moisture leakages in the environment that might cause swelling of the bentonite blocks during the 'open' installation phase before backfilling. The purpose of this work was to design the structural reference solution both for the bottom of the deposition hole and for the buffer moisture protection and dewatering system with their integrated equipment needed in the deposition hole. This report describes the Posiva's reference solution for the buffer moisture protection system and the bottom plate on basis of the demands and functional requirements set by long-term safety. The reference solution with structural details has been developed in research work made 2010-2011. The structural solution of the moisture protection system has not yet been tested in practice. On the bottom of the deposition hole a copper plate which protects the lowest bentonite block from the gathered water is installed straight to machined and even rock surface. The moisture protection sheet made of EPDM rubber is attached to the copper plate with an inflatable seal. The upper part of the moisture protection sheet is fixed to the collar structures of the lid which protects the deposition hole in the disposal tunnel. The main function of the moisture protection sheet is to protect bentonite blocks from the leaking water and from the influence of the air humidity at their installation stage. The leaking water is controlled by the dewatering and alarm system which has been integrated into the moisture protection liner. (orig.)

  19. Tensile creep and recovery of Norway spruce influenced by temperature and moisture

    DEFF Research Database (Denmark)

    Engelund, Emil Tang; Salmén, Lennart

    2012-01-01

    of these two climatic factors on TDMB of wood. It was found that the mechanical response of wood tissue is the sum of responses from both tracheids and middle lamella, with only the previous being reversible. The effect of moisture and temperature differed in that the latter affected the elastic and time...

  20. Microcomputerized neutron moisture gauge

    International Nuclear Information System (INIS)

    Liu Shengkang; Mei Yu

    1987-01-01

    A microcomputerized neutron moisture gauge is introduced. This gauge consists of a neutron moisture sensor and instruments. It is developed from the neutron moisture gauge for concrete mixer. A TECH-81 single card microcomputer is used for count, computation and display. It has the function of computing compensated quantity of sand. It can acquire the data from several neutron sensors by the multichanneling sampling, therefore it can measure moisture values of sand in several hoppers simultaneously. The precision of the static state calibration curve is 0.24% wt. The error limits of the dynamic state check is < 0.50% wt

  1. Effect of Initial Moisture on the Adsorption and Desorption Equilibrium Moisture Contents of Polished Rice

    OpenAIRE

    Murata, Satoshi; Amaratunga, K.S.P.; Tanaka, Fumihiko; Hori, Yoshiaki; 村田, 敏; 田中, 史彦; 堀, 善昭

    1993-01-01

    The moisture adsorption and desorption properties for polished rice have been measured using a dynamic ventilatory method. Air temperatures of 10,20,30 and 40℃, relative humidities of 50,60,70,80 and 90%, and five levels of initial moisture contents ranging approximately from 8% to 19% d.b. were used to obtain moisture content data. The value of equilibrium moisture content for each initial moisture content at the range of air condition was determined by a method of nonlinear least squares. R...

  2. Moisture content measurement in paddy

    Science.gov (United States)

    Klomklao, P.; Kuntinugunetanon, S.; Wongkokua, W.

    2017-09-01

    Moisture content is an important quantity for agriculture product, especially in paddy. In principle, the moisture content can be measured by a gravimetric method which is a direct method. However, the gravimetric method is time-consuming. There are indirect methods such as resistance and capacitance methods. In this work, we developed an indirect method based on a 555 integrated circuit timer. The moisture content sensor was capacitive parallel plates using the dielectric constant property of the moisture. The instrument generated the output frequency that depended on the capacitance of the sensor. We fitted a linear relation between periods and moisture contents. The measurement results have a standard uncertainty of 1.23 % of the moisture content in the range of 14 % to 20 %.

  3. Portable neutron moisture gage for the moisture determination of structure parts

    International Nuclear Information System (INIS)

    Harnisch, M.

    1985-01-01

    For determining the moisture of structure parts during building or before repairing a portable neutron moisture gage consisting of a neutron probe and pulse analyzer has been developed. The measuring process, calibration, and prerequisites of application are briefly discussed

  4. Equilibrium moisture content (EMC) in Norway spruce during the first and second desorptions

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Engelund, Emil Tang; Thygesen, Lisbeth G.

    2011-01-01

    It is a commonly accepted notion that the equilibrium moisture content (EMC) of wood at a given relative humidity (RH) is highest during initial desorption of green wood due to an irreversible loss of hygroscopicity during the 1st desorption. The basis for this notion is investigated by assessing...

  5. Cell wall domain and moisture content influence southern pine electrical conductivity

    Science.gov (United States)

    Samuel L. Zelinka; Leandro Passarini; José L. Colon Quintana; Samuel V. Glass; Joseph E. Jakes; Alex C. Wiedenhoeft

    2016-01-01

    Recent work has highlighted the importance of movement of chemicals and ions through the wood cell wall. This movement depends strongly on moisture content and is necessary for structural damage mechanisms such as fastener corrosion and wood decay. Here, we present the first measurements of electrical resistance of southern pine at the subcellular level as a function...

  6. A multivariate mixed model system for wood specific gravity and moisture content of planted loblolly pine stands in the southern United States

    Science.gov (United States)

    Finto Antony; Laurence R. Schimleck; Alex Clark; Richard F. Daniels

    2012-01-01

    Specific gravity (SG) and moisture content (MC) both have a strong influence on the quantity and quality of wood fiber. We proposed a multivariate mixed model system to model the two properties simultaneously. Disk SG and MC at different height levels were measured from 3 trees in 135 stands across the natural range of loblolly pine and the stand level values were used...

  7. Effects of moisture barrier and initial moisture content on the storage ...

    African Journals Online (AJOL)

    The two factors examined were moisture barrier at three levels namely: thick lining, thin lining and non-lining. The other factor included initial moisture content of the produce, namely, turgid and partially wilted. Partial wilting of the produce was achieved by exposing freshly harvested materials at ambient temperature to dry ...

  8. 7 CFR 52.3185 - Moisture limits.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Moisture limits. 52.3185 Section 52.3185 Agriculture... United States Standards for Grades of Dried Prunes Moisture, Uniformity of Size, Defects § 52.3185 Moisture limits. Dried prunes shall not exceed the moisture limits for the applicable grades and kind and...

  9. The challenge of bonding treated wood

    Science.gov (United States)

    Charles R. Frihart

    2004-01-01

    Wood products are quite durable if exposure to moisture is minimized; however, most uses of wood involve considerable exposure to moisture. To preserve the wood, chemicals are used to minimize moisture pickup, to prevent insect attack, and/or to resist microbial growth. The chemicals used as preservatives can interfere with adhesive bonds to wood. Given the many...

  10. 7 CFR 868.258 - Moisture.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Moisture. 868.258 Section 868.258 Agriculture... Governing Application of Standards § 868.258 Moisture. Water content in brown rice for processing as... purpose of this paragraph, “approved device” shall include the Motomco Moisture Meter and any other...

  11. Errors in the calculation of sub-soil moisture probe by equivalent moisture content technique

    International Nuclear Information System (INIS)

    Lakshmipathy, A.V.; Gangadharan, P.

    1982-01-01

    The size of the soil sample required to obtain the saturation response, with a neutron moisture probe is quite large and this poses practical problems of handling and mixing large amounts of samples for absolute laboratory calibration. Hydrogenous materials are used as a substitute for water in the equivalent moisture content technique, for calibration of soil moisture probes. In this it is assumed that only hydrogen of the bulk sample is responsible for the slowing down of fast neutrons and the slow neutron countrate is correlated to equivalent water content by considering the hydrogen density of sample. It is observed that the higher atomic number elements present in water equivalent media also affect the response of the soil moisture probe. Hence calculations, as well as experiments, were undertaken to know the order of error introduced by this technique. The thermal and slow neutron flux distribution around the BF 3 counter of a sub-soil moisture probe is calculated using three group diffusion theory. The response of the probe corresponding to different equivalent moisture content of hydrogenous media, is calculated taking into consideration the effective length of BF 3 counter. Soil with hydrogenous media such as polyethylene, sugar and water are considered for calculation, to verify the suitability of these materials as substitute for water during calibration of soil moisture probe. Experiments were conducted, to verify the theoretically calculated values. (author)

  12. Soil moisture variability across different scales in an Indian watershed for satellite soil moisture product validation

    KAUST Repository

    Singh, Gurjeet

    2016-05-05

    Strategic ground-based sampling of soil moisture across multiple scales is necessary to validate remotely sensed quantities such as NASA’s Soil Moisture Active Passive (SMAP) product. In the present study, in-situ soil moisture data were collected at two nested scale extents (0.5 km and 3 km) to understand the trend of soil moisture variability across these scales. This ground-based soil moisture sampling was conducted in the 500 km2 Rana watershed situated in eastern India. The study area is characterized as sub-humid, sub-tropical climate with average annual rainfall of about 1456 mm. Three 3x3 km square grids were sampled intensively once a day at 49 locations each, at a spacing of 0.5 km. These intensive sampling locations were selected on the basis of different topography, soil properties and vegetation characteristics. In addition, measurements were also made at 9 locations around each intensive sampling grid at 3 km spacing to cover a 9x9 km square grid. Intensive fine scale soil moisture sampling as well as coarser scale samplings were made using both impedance probes and gravimetric analyses in the study watershed. The ground-based soil moisture samplings were conducted during the day, concurrent with the SMAP descending overpass. Analysis of soil moisture spatial variability in terms of areal mean soil moisture and the statistics of higher-order moments, i.e., the standard deviation, and the coefficient of variation are presented. Results showed that the standard deviation and coefficient of variation of measured soil moisture decreased with extent scale by increasing mean soil moisture. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  13. Moisture accumulation in a building envelope

    Energy Technology Data Exchange (ETDEWEB)

    Forest, T.W.; Checkwitch, K.

    1988-09-01

    In a large number of cases, the failure of a building envelope can be traced to the accumulation of moisture. In a cold winter climate, characteristic of the Canadian prairies, moisture is deposited in the structure by the movement of warm, moist air through the envelope. Tests on the moisture accumulation in a building envelope were initiated in a test house at an Alberta research facility during the 1987/88 heating season. The indoor moisture generation rate was measured and compared with the value inferred from the measured air infiltration rate. With the flue open, the moisture generation rate was approximately 5.5 kg/d of which 0.7 kg/d entered the building envelope; the remainder was exhausted through the flue. With the flue blocked, the moisture generation rate decreased to 3.4 kg/d, while the amount of moisture migrating through the envelope increased to 4.0 kg/d. The moisture accumulation in wall panels located on the north and south face of the test house was also monitored. Moisture was allowed to enter the wall cavity via a hole in the drywall. The fiberglass insulation remained dry throughout the test period. The moisture content of the exterior sheathing of the north panel increased to a maximum of 18% wt in the vicinity of the hole, but quickly dried when the ambient temperatures increased towards the end of the season. The south panel showed very little moisture accumlation due to the effects of solar radiation. 14 refs., 9 figs.

  14. Use of Soil Moisture Variability in Artificial Neural Network Retrieval of Soil Moisture

    Directory of Open Access Journals (Sweden)

    Bert Veenendaal

    2009-12-01

    Full Text Available Passive microwave remote sensing is one of the most promising techniques for soil moisture retrieval. However, the inversion of soil moisture from brightness temperature observations is not straightforward, as it is influenced by numerous factors such as surface roughness, vegetation cover, and soil texture. Moreover, the relationship between brightness temperature, soil moisture and the factors mentioned above is highly non-linear and ill-posed. Consequently, Artificial Neural Networks (ANNs have been used to retrieve soil moisture from microwave data, but with limited success when dealing with data different to that from the training period. In this study, an ANN is tested for its ability to predict soil moisture at 1 km resolution on different dates following training at the same site for a specific date. A novel approach that utilizes information on the variability of soil moisture, in terms of its mean and standard deviation for a (sub region of spatial dimension up to 40 km, is used to improve the current retrieval accuracy of the ANN method. A comparison between the ANN with and without the use of the variability information showed that this enhancement enables the ANN to achieve an average Root Mean Square Error (RMSE of around 5.1% v/v when using the variability information, as compared to around 7.5% v/v without it. The accuracy of the soil moisture retrieval was further improved by the division of the target site into smaller regions down to 4 km in size, with the spatial variability of soil moisture calculated from within the smaller region used in the ANN. With the combination of an ANN architecture of a single hidden layer of 20 neurons and the dual-polarized brightness temperatures as input, the proposed use of variability and sub-region methodology achieves an average retrieval accuracy of 3.7% v/v. Although this accuracy is not the lowest as comparing to the research in this field, the main contribution is the ability of ANN in

  15. Moisture Dynamics in Building Envelopes

    DEFF Research Database (Denmark)

    Peuhkuri, Ruut Hannele

    2003-01-01

    The overall scope of this Thesis "Moisture dynamics in building envelopes" has been to characterise how the various porous insulation materials investigated performed hygrothermally under conditions similar to those in a typical building envelope. As a result of the changing temperature...... part of the Thesis consists of a theory and literature review on the moisture storage and transport processes (Chapter 2), on the non-Fickian moisture transport (Chapter 3)and on the methods for determining the moisture properties (Chapter 4). In the second part, the conducted experimental work...

  16. Moisture dynamics in building envelopes

    Energy Technology Data Exchange (ETDEWEB)

    Peuhkuri, R.

    2003-07-01

    The overall scope of this Thesis 'Moisture dynamics in building envelopes' has been to characterise how the various porous insulation materials investigated performed hygro thermally under conditions similar to those in a typical building envelope. As a result of the changing temperature and moisture conditions in the exterior weather and indoor climate the materials dynamically absorb and release moisture. The complexity of the impact of these conditions on the resulting moisture transport and content of the materials has been studied in this Thesis with controlled laboratory tests. (au)

  17. 7 CFR 868.207 - Moisture.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Moisture. 868.207 Section 868.207 Agriculture... Application of Standards § 868.207 Moisture. Water content in rough rice as determined by an approved device..., “approved device” shall include the Motomco Moisture Meter and any other equipment that is approved by the...

  18. Soil moisture variability across different scales in an Indian watershed for satellite soil moisture product validation

    KAUST Repository

    Singh, Gurjeet; Panda, Rabindra K.; Mohanty, Binayak P.; Jana, Raghavendra Belur

    2016-01-01

    Strategic ground-based sampling of soil moisture across multiple scales is necessary to validate remotely sensed quantities such as NASA’s Soil Moisture Active Passive (SMAP) product. In the present study, in-situ soil moisture data were collected

  19. Equilibrium moisture content of radiata pine at elevated temperature and pressure reveals measurement challenges

    DEFF Research Database (Denmark)

    Pearson, Hamish; Gabbitas, Brian; Ormarsson, Sigurdur

    2012-01-01

    moisture contents were attributed to condensation of liquid water on the specimen with subsequent evaporation at a rate that was too slow for the moisture content to reach equilibrium before it was measured. Reliable EMC data at elevated temperatures require (1) tight process control of experimental......Relatively few studies have been performed on the equilibrium moisture content (EMC) of wood under conditions of elevated temperature and pressure. Eight studies indicated that EMC near saturation decreased between 100 and 150 °C, whilst five studies indicated that EMC increased. The aim...... of this study was to identify the likely source of the disagreement using radiata pine (Pinus radiata D. Don) sapwood which was conditioned to a moisture content of around 3 % and then exposed for 1 h at 150 °C and relative humidities of either 50, 70 or 90 %. Mean values of EMC, obtained through in situ...

  20. Moisture content determination in solid biofuels by dielectric and NIR reflection methods

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Peter Daugbjerg; Morsing, Merete [Department of Forest and Landscape, The Royal Veterinary and Agricultural University, Rolighedsvej 23, DK-1958 Frederiksberg C (Denmark); Hartmann, Hans; Boehm, Thorsten [Technologie- und Foerderzentrum fuer Nachwachsende Rohstoffe (TFZ), Schulgasse 18, D-94315 Straubing (Germany); Temmerman, Michael; Rabier, Fabienne [Departement Genie Rural, Chee de Namur 146, B-5030 Gembloux (Belgium)

    2006-11-15

    One near infrared (NIR) reflectance and five dielectric moisture meters were tested for their capability of measuring moisture content (MC) in solid biofuels. Ninety-eight samples were tested at up to eight moisture levels covering the MC range from fresh fuel to approximately 10% MC (w.b.). The fuel types ranged from typical solid biofuels such as coniferous and deciduous wood chips over short rotation coppice (SRC) to sunflower seed and olive stones. The most promising calibrations were obtained with the NIR reflection method and two dielectric devices where the sample is placed in a container integrated in the device. The calibration equations developed show that there is a profound influence from both laboratory and fuel type. It is suggested that individual calibrations that are based on the specific fuel types used at the individual heating plant could be applied. (author)

  1. Long term durability of wood-plastic composites made with chemically modified wood

    Science.gov (United States)

    Rebecca E. Ibach; Craig M. Clemons

    2017-01-01

    Wood-plastic composites (WPCs) have slower moisture sorption than solid wood, but over time moisture can impact the strength, stiffness, and decay of the composite. These changes will become increasingly important if WPCs are used in more challenging environments such as in ground-contact applications. There are several options for mitigating the moisture sorption of...

  2. Moisture management, energy density and fuel quality in forest fuel supply chains

    Energy Technology Data Exchange (ETDEWEB)

    Tahvanainen, T. [Joensuu Science Park Ltd., Joensuu (Finland); Sikanen, L. [Joensuu Univ. (Finland); Roser, D. [Finnish Forest Research Inst., Joensuu (Finland)

    2009-07-01

    This presentation provided tools for reducing the moisture content (MC) in wood chips, as moisture is one of the main quality factors for woody biomass, along with energy density and cleanness. The amount of water in solid wood fuels has a considerable effect on transportation efficiency, combustion efficiency and emissions. Under favourable storage conditions, MC can be decreased from typical fresh cut 50-55 per cent to 20-30 per cent in relatively short periods of storing by natural or artificial drying. Minor modifications can boost natural drying in fuel wood supply chains. This natural drying effect can have significant effects on the total energy efficiency and emissions of supply chains. The effect of improved packing density on transportation phase was discussed along with the need to control chip purity and size distribution. A procedure developed at the University of Joensuu and in the Finnish Forest Research Institute was used to estimate transportation costs and emissions according to transportation fleet and MC of the transported fuel. tabs., figs.

  3. 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

  4. Moisture measurements in building materials with microwaves; Rakennusmateriaalien kosteusmittauksia mikroaalloilla

    Energy Technology Data Exchange (ETDEWEB)

    Kaeaeriaeinen, H.; Rudolph, M.; Schaurich, D.; Wiggenhauser, H. [VTT Building Technology, Espoo (Finland). Construction and Facility Management

    1998-12-01

    In order to assess the condition and evaluate the reliability of buildings and structures, it is essential to establish the moisture condition of the floor and other structural elements of the building. NDT-methods are increasingly being used for such moisture measurements because they do not cause any damage to the building under investigation. Microwave transmission is one of the NDT-methods and has been in use for several years. In this report, the applicability of the microwave method for measuring moisture in different building materials was investigated. This method has been successfully used at BAM for repeated moisture measurements in brick and sandstone material. This project also included other materials, such as concrete, sand, gravel, insulation and wood. At the same time, information was gathered about in situ moisture determination of building materials with a microwave moisture measuring system. The equipment used in this research has been developed at BAM over the last few years. The method requires two parallel boreholes in the specimen in which two microwave antennae can be moved. The moisture content in the material can be calculated from the microwave intensity transmitted between the two boreholes. Moisture profiles along the boreholes can be obtained by moving the antennae in steps along the length of the boreholes and taking measurements at each step. Special care must be taken while drilling the holes for the antennae, as this process must not affect the moisture condition in the specimen, and the boreholes must be made as parallel to each other as possible. The microwave frequencies used in the laboratory measurements ranged from 8 to 16,5 GHz in steps of 0,5 GHz. The diameters of the antennae were between 7 and 9 mm, and of the boreholes between 8 and 12 mm. Except for the concrete specimen, all the specimens were measured using plastic tubes in the boreholes. The moisture content measured by the microwave technique was verified by the

  5. Measurement of soil moisture using gypsum blocks

    DEFF Research Database (Denmark)

    Friis Dela, B.

    the building. Consequently, measuring the moisture of the surrounding soil is of great importance for detecting the source of moisture in a building. Up till now, information has been needed to carry out individual calibrations for the different types of gypsum blocks available on the market and to account......For the past 50 years, gypsum blocks have been used to determine soil moisture content. This report describes a method for calibrating gypsum blocks for soil moisture measurements. Moisture conditions inside a building are strongly influenced by the moisture conditions in the soil surrounding...

  6. Tensile behaviour of radiata pine with different moisture contents at elevated temperatures

    DEFF Research Database (Denmark)

    Pearson, Hamish; Gabbitas, Brian; Ormarsson, Sigurdur

    2012-01-01

    that moisture and temperature can play a significant role in reducing stress during drying, regardless of the drying time. Properties of wood, such as tensile elastic information at elevated temperatures, are important for mechanical design, distortion modelling and understanding the fundamental behaviour...

  7. Probing bias reduction to improve comparability of lint cotton water and moisture contents at moisture equilibrium

    Science.gov (United States)

    The Karl Fischer Titration (KFT) reference method is specific for water in lint cotton and was designed for samples conditioned to moisture equilibrium, thus limiting its biases. There is a standard method for moisture content – weight loss – by oven drying (OD), just not for equilibrium moisture c...

  8. Stress-wave velocity of wood-based panels: effect of moisture, product type, and material direction

    Science.gov (United States)

    Guangping Han; Qinglin Wu; Xiping Wang

    2006-01-01

    The effect of moisture on longitudinal stress-wave velocity (SWV), bending stiffness. and bending strength of commercial oriented strandboard, plywood. particleboard. and southern pine lumber was evaluated. It was shown that the stress-wave verocity decreased in general with increases in panel moisture content (MC). At a given MC level. SWV varied with panel type and...

  9. An overview of the measurements of soil moisture and modeling of moisture flux in FIFE

    Science.gov (United States)

    Wang, J. R.

    1992-01-01

    Measurements of soil moisture and calculations of moisture transfer in the soil medium and at the air-soil interface were performed over a 15-km by 15-km test site during FIFE in 1987 and 1989. The measurements included intensive soil moisture sampling at the ground level and surveys at aircraft altitudes by several passive and active microwave sensors as well as a gamma radiation device.

  10. Compact RFID Enabled Moisture Sensor

    Directory of Open Access Journals (Sweden)

    U. H. Khan

    2016-09-01

    Full Text Available This research proposes a novel, low-cost RFID tag sensor antenna implemented using commercially available Kodak photo-paper. The aim of this paper is to investigate the possibility of stable, RFID centric communication under varying moisture levels. Variation in the frequency response of the RFID tag in presence of moisture is used to detect different moisture levels. Combination of unique jaw shaped contours and T-matching network is used for impedance matching which results in compact size and minimal ink consumption. Proposed tag is 1.4 × 9.4 cm2 in size and shows optimum results for various moisture levels upto 45% in FCC band with a bore sight read range of 12.1 m.

  11. Neutron moisture monitoring (NMM) and moisture contents in the Green River, Utah, UMTRA disposal cell

    International Nuclear Information System (INIS)

    1992-06-01

    This report provides the basis for the US Department of Energy's (DOE) request to discontinue neutron moisture monitoring (NMM) at the Green River, Utah, Uranium Mill Tailings Remedial Action (UMTRA) disposal cell and decommission the neutron access holes. After 3 years of monitoring the disposal cell, the DOE has determined that the NMM method is not suitable for determining changes in moisture content in the disposal cell. Existing tailings moisture contents in the disposal cell result in a low seepage flux. The combination of a low seepage flux and geochemical retardation by foundation materials underneath the disposal cell ensures that the proposed US Environmental Protection Agency (EPA) groundwater protection standards will not be exceeded within the design life of the disposal cell. To assess the effectiveness of the NMM method for monitoring moisture contents In the disposal cell at Green River, the DOE subsequently conducted a field study and a review of historical and new literature. The literature review allowed the DOE to identify performance criteria for the NMM method. Findings of these studies suggest that: The NMM method is not sensitive to the low moisture contents found in the disposal cell.; there is an insufficient range of moisture contents in the disposal cell to develop a field calibration curve relating moisture content to neutron counts; it is not possible to collect NMM data from the disposal cell that meet data quality objectives for precision and accuracy developed from performance criteria described in the literature

  12. Moisture-induced stresses in glulam frames

    DEFF Research Database (Denmark)

    Ormarsson, Sigurdur; Gislason, Oskar V

    2016-01-01

    by hand. Accordingly, there is a need for advanced computer tools to study how the long-term stress behaviour of timber structures is affected by creep and cyclic variations in climate. A beam model to simulate the overall hygro-mechanical and visco-elastic behaviour of (inhomogeneous) glulam structures...... is presented. A two-dimensional transient, non-linear moisture transport model for wood is also developed and linked with this beam model. The combined models are used to study the long-term deformations and stresses in a curved frame structure exposed to both mechanical loading and cyclic climate conditions...

  13. On-irrigator pasture soil moisture sensor

    International Nuclear Information System (INIS)

    Tan, Adrian Eng-Choon; Richards, Sean; Platt, Ian; Woodhead, Ian

    2017-01-01

    In this paper, we presented the development of a proximal soil moisture sensor that measured the soil moisture content of dairy pasture directly from the boom of an irrigator. The proposed sensor was capable of soil moisture measurements at an accuracy of  ±5% volumetric moisture content, and at meter scale ground area resolutions. The sensor adopted techniques from the ultra-wideband radar to enable measurements of ground reflection at resolutions that are smaller than the antenna beamwidth of the sensor. An experimental prototype was developed for field measurements. Extensive field measurements using the developed prototype were conducted on grass pasture at different ground conditions to validate the accuracy of the sensor in performing soil moisture measurements. (paper)

  14. Moisture measurement in the iron and steel industry: experience with nuclear moisture measurements in coke, and studies of infrared moisture measurement of iron ore mixtures

    International Nuclear Information System (INIS)

    Beumer, J.A.; Wouters, M.

    1976-01-01

    In the heavy iron-making industry there are several processes for which it is necessary to measure on-line the moisture content of certain process materials, especially in the field of iron ore preparation and blast furnace practice. Two examples are given. (1) Experience with nuclear moisture-measurements in coke covers a period of ten years in which eight measuring systems have been installed in the weighing hoppers of blast furnaces. The standard deviation is about 0.7% moisture in the range 0 to 15% moisture. The way the method is used, the safety measures and the difficulties encountered, especially the effect on recalibration of neutron-absorbing materials in photomultipliers are described. (2) The application of infrared absorption to the study of moisture measurment or iron ore mixtures is described. With an ore mixture for pellets manufacture, a rather dark ore mixture, problems have arisen concerning the sensitivity. The reference and measuring wavelengths now in use are 2.51 and 2.95 μm. In this case the absorption of the energy is rather high. The results may be improved by using quartz optics instead of the normal Pyrex ones, as the cut-off wavelength of Pyrex is about 3 μm. Variations due to colour and specific surface have been studied. As the accuracy required is +- 0.1% moisture in the range 8 to 12% moisture, these variations need to be eliminated. (author)

  15. Development of a neutron moisture gauge

    International Nuclear Information System (INIS)

    Prasad, A.S.

    1979-01-01

    A neutron moisture gauge fabricated for measuring the moisture content of coke is described. It has an americium-beryllium source placed beside a boron coated neutron counter which is a slow neutron detector. The fast neutrons emitted by the radioactive source are slowed down by the hydrogen nuclei present in the material either as bound hydrogen or as a hydrogen of the water. Measure of the slowed down i.e. thermal neutrons (their density) is proportional to the total hydrogen content of the material. The instrument is installed as an ''on-line'' measuring device to estimate the moisture content of coke at the weighing hopper feeding the skip car. The accuracy of measurement is dependent on the moisture content, i.e. higher accuracy is obtained for higher moisture content. At low moisture content, the effect of the bound hydrogen other than that of the water on low moisture readings is pronounced. Effect of bulk density on the accuracy of measurement is not very significant as long as the coke size is constant. The error is in the range of +- 1.1%. (M.G.B.)

  16. Moisture performance properties of exterior sheathing products made of spruce plywood or OSB

    Energy Technology Data Exchange (ETDEWEB)

    Ojanen, T.; Ahonen, J. [VTT Building and Transport, Espoo (Finland)

    2005-02-01

    Plywood and OSB (Oriented Strand Board) are building boards that are made of timber and glue and that have good structural strength. OSB is a relatively new product that is produced from various timber materials and even some wastewood can be used as raw material for this product. Due to the easy access of raw material and economical reasons, the use of OSB has been highly increasing. The moisture safety of the building envelope depends on the properties of the building products. The moisture performance properties of the sheathing boards have not got enough attention, too often these wood based materials are equated without considering the real properties and their effect on the overall moisture performance. This research was carried out to experimentally determine the material properties and performance characteristics that have an effect on the moisture performance of building structures where OSB or spruce plywood are applied as exterior sheathing boards. A relatively representative amount of samples were used to study the moisture properties of European OSB and plywood products and a comparison to one Canadian OSB and one plywood product was done. All the products used in this research were meant to be used also as exterior sheathing boards. The results shows clearly the differences between OSB and plywood products. The products are not interchangeable. The main differences can be found from the vapour permeability levels that have an effect on the drying efficiency of building structures. The products have different performance criteria, and the climate conditions and moisture loads have to be studied to evaluate their suitability and moisture safety aspects in different applications. Water repellent features and drying efficiency are somewhat opposite properties of the products and the dimensional changes under varying moisture contents can set some boundary conditions when the optimum solution for the exterior sheathing is considered. (orig.)

  17. Multilayer moisture barrier

    Science.gov (United States)

    Pankow, Joel W; Jorgensen, Gary J; Terwilliger, Kent M; Glick, Stephen H; Isomaki, Nora; Harkonen, Kari; Turkulainen, Tommy

    2015-04-21

    A moisture barrier, device or product having a moisture barrier or a method of fabricating a moisture barrier having at least a polymer layer, and interfacial layer, and a barrier layer. The polymer layer may be fabricated from any suitable polymer including, but not limited to, fluoropolymers such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), or ethylene-tetrafluoroethylene (ETFE). The interfacial layer may be formed by atomic layer deposition (ALD). In embodiments featuring an ALD interfacial layer, the deposited interfacial substance may be, but is not limited to, Al.sub.2O.sub.3, AlSiO.sub.x, TiO.sub.2, and an Al.sub.2O.sub.3/TiO.sub.2 laminate. The barrier layer associated with the interfacial layer may be deposited by plasma enhanced chemical vapor deposition (PECVD). The barrier layer may be a SiO.sub.xN.sub.y film.

  18. Contributions of Precipitation and Soil Moisture Observations to the Skill of Soil Moisture Estimates in a Land Data Assimilation System

    Science.gov (United States)

    Reichle, Rolf H.; Liu, Qing; Bindlish, Rajat; Cosh, Michael H.; Crow, Wade T.; deJeu, Richard; DeLannoy, Gabrielle J. M.; Huffman, George J.; Jackson, Thomas J.

    2011-01-01

    The contributions of precipitation and soil moisture observations to the skill of soil moisture estimates from a land data assimilation system are assessed. Relative to baseline estimates from the Modern Era Retrospective-analysis for Research and Applications (MERRA), the study investigates soil moisture skill derived from (i) model forcing corrections based on large-scale, gauge- and satellite-based precipitation observations and (ii) assimilation of surface soil moisture retrievals from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E). Soil moisture skill is measured against in situ observations in the continental United States at 44 single-profile sites within the Soil Climate Analysis Network (SCAN) for which skillful AMSR-E retrievals are available and at four CalVal watersheds with high-quality distributed sensor networks that measure soil moisture at the scale of land model and satellite estimates. The average skill (in terms of the anomaly time series correlation coefficient R) of AMSR-E retrievals is R=0.39 versus SCAN and R=0.53 versus CalVal measurements. The skill of MERRA surface and root-zone soil moisture is R=0.42 and R=0.46, respectively, versus SCAN measurements, and MERRA surface moisture skill is R=0.56 versus CalVal measurements. Adding information from either precipitation observations or soil moisture retrievals increases surface soil moisture skill levels by IDDeltaR=0.06-0.08, and root zone soil moisture skill levels by DeltaR=0.05-0.07. Adding information from both sources increases surface soil moisture skill levels by DeltaR=0.13, and root zone soil moisture skill by DeltaR=0.11, demonstrating that precipitation corrections and assimilation of satellite soil moisture retrievals contribute similar and largely independent amounts of information.

  19. Absolute moisture sensing for cotton bales

    Science.gov (United States)

    With the recent prevalence of moisture restoration systems in cotton gins, more and more gins are putting moisture back into the bales immediately before the packaging operation. There are two main reasons for this recent trend, the first is that it has been found that added moisture at the bale pre...

  20. Stress wave velocity and dynamic modulus of elasticity of yellow-poplar ranging from 100 to 10 percent moisture content

    Science.gov (United States)

    Jody D. Gray; Shawn T. Grushecky; James P. Armstrong

    2008-01-01

    Moisture content has a significant impact on mechanical properties of wood. In recent years, stress wave velocity has been used as an in situ and non-destructive method for determining the stiffness of wooden elements. The objective of this study was to determine what effect moisture content has on stress wave velocity and dynamic modulus of elasticity. Results...

  1. MOISTURE-BUFFERING CHARACTERISTICS OF BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    Young Cheol Choi

    2016-05-01

    Full Text Available The humidity level of indoor air is an important factor influencing the air quality and energy consumption of buildings, as well as the durability of building components. Indoor humidity levels depend on several factors, such as moisture sources, air flow, and the adsorption/desorption properties of materials. The moisture-buffering characteristics of building materials that are in contact with indoor air may help moderate the variations of indoor humidity, especially in the summer and winter. In this study, the moisture adsorption/desorption properties of building materials were investigated experimentally and numerically. These properties can be used to characterize the ability of building materials to exchange moisture with the indoor environment. This study indicates that a building material surface resistivity was the main factor creating variations of moisture buffering.

  2. Moisture problems of functional joints of wooden windows – causes analysis

    Directory of Open Access Journals (Sweden)

    Palková Adela

    2018-01-01

    Full Text Available The article addresses the issue of the humidity regimen of a functional wooden window joint. Current energy-saving trends in the buildings bring secondary effects associated with indoor climate change. Increase of the thermal-technical quantification, non-breathability, and diffusion resistance of the building envelope without the solution of controlled ventilation brings an extreme rise of the interior moisture. The passage of moisture through a functional joint is ensured mainly by exfiltration. The energy standard applicable after the year 2020 assumes buildings with almost zero energy need that cannot be reached without a recuperation system. The concept of the recuperation systems usually works as a pressure system, which increases the likelihood of exfiltration. Measurements done in a large climate chamber show that the diffusion of water vapor can overcome the infiltration flow of the outside air. The passage of moisture results in icing or condensation in the functional joint, which subsequently damages the surface treatment of the wood. Another serious defect is the subsequent mold growth.

  3. Interior moisture design loads for residences

    Science.gov (United States)

    Anton TenWolde; Iain S. Walker

    2001-01-01

    This paper outlines a methodology to obtain design values for indoor boundary conditions for moisture design calculations for residences. This is part of a larger effort by ASHRAE Standard Project Committee 160P, Design Criteria for Moisture Control in Buildings, to formulate criteria for moisture design loads, analysis techniques, and material and building performance...

  4. Australian Soil Moisture Field Experiments in Support of Soil Moisture Satellite Observations

    Science.gov (United States)

    Kim, Edward; Walker, Jeff; Rudiger, Christopher; Panciera, Rocco

    2010-01-01

    Large-scale field campaigns provide the critical fink between our understanding retrieval algorithms developed at the point scale, and algorithms suitable for satellite applications at vastly larger pixel scales. Retrievals of land parameters must deal with the substantial sub-pixel heterogeneity that is present in most regions. This is particularly the case for soil moisture remote sensing, because of the long microwave wavelengths (L-band) that are optimal. Yet, airborne L-band imagers have generally been large, heavy, and required heavy-lift aircraft resources that are expensive and difficult to schedule. Indeed, US soil moisture campaigns, have been constrained by these factors, and European campaigns have used non-imagers due to instrument and aircraft size constraints. Despite these factors, these campaigns established that large-scale soil moisture remote sensing was possible, laying the groundwork for satellite missions. Starting in 2005, a series of airborne field campaigns have been conducted in Australia: to improve our understanding of soil moisture remote sensing at large scales over heterogeneous areas. These field data have been used to test and refine retrieval algorithms for soil moisture satellite missions, and most recently with the launch of the European Space Agency's Soil Moisture Ocean Salinity (SMOS) mission, to provide validation measurements over a multi-pixel area. The campaigns to date have included a preparatory campaign in 2005, two National Airborne Field Experiments (NAFE), (2005 and 2006), two campaigns to the Simpson Desert (2008 and 2009), and one Australian Airborne Cal/val Experiment for SMOS (AACES), just concluded in the austral spring of 2010. The primary airborne sensor for each campaign has been the Polarimetric L-band Microwave Radiometer (PLMR), a 6-beam pushbroom imager that is small enough to be compatible with light aircraft, greatly facilitating the execution of the series of campaigns, and a key to their success. An

  5. Effectiveness of modified 1-hour air-oven moisture methods for determining popcorn moisture

    Science.gov (United States)

    Two of the most commonly used approved grain moisture air-oven reference methods are the air oven method ASAE S352.2, which requires long heating time (72-h) for unground samples, and the AACC 44-15.02 air-oven method, which dries a ground sample for 1 hr, but there is specific moisture measurement ...

  6. Digital radioisotope moisture-density meter

    International Nuclear Information System (INIS)

    Bychvarov, N.; Vankov, I.; Dimitrov, L.

    1982-01-01

    The primary information from the detectors of a combined radioisotope moisture-density meter is obtained as pulses, their counting rate being functionally dependent on the humidity per unit volume and the wet density. However, most practical cases demand information on the moisture per unit weight and the mass density of the dry skeleton. The paper describes how the proposed electronic circuit processes the input primary information to obtain the moisture in weight % and the mass density of the dry skeleton in g/cm 3 . (authors)

  7. Modeling soil moisture memory in savanna ecosystems

    Science.gov (United States)

    Gou, S.; Miller, G. R.

    2011-12-01

    Antecedent soil conditions create an ecosystem's "memory" of past rainfall events. Such soil moisture memory effects may be observed over a range of timescales, from daily to yearly, and lead to feedbacks between hydrological and ecosystem processes. In this study, we modeled the soil moisture memory effect on savanna ecosystems in California, Arizona, and Africa, using a system dynamics model created to simulate the ecohydrological processes at the plot-scale. The model was carefully calibrated using soil moisture and evapotranspiration data collected at three study sites. The model was then used to simulate scenarios with various initial soil moisture conditions and antecedent precipitation regimes, in order to study the soil moisture memory effects on the evapotranspiration of understory and overstory species. Based on the model results, soil texture and antecedent precipitation regime impact the redistribution of water within soil layers, potentially causing deeper soil layers to influence the ecosystem for a longer time. Of all the study areas modeled, soil moisture memory of California savanna ecosystem site is replenished and dries out most rapidly. Thus soil moisture memory could not maintain the high rate evapotranspiration for more than a few days without incoming rainfall event. On the contrary, soil moisture memory of Arizona savanna ecosystem site lasts the longest time. The plants with different root depths respond to different memory effects; shallow-rooted species mainly respond to the soil moisture memory in the shallow soil. The growing season of grass is largely depended on the soil moisture memory of the top 25cm soil layer. Grass transpiration is sensitive to the antecedent precipitation events within daily to weekly timescale. Deep-rooted plants have different responses since these species can access to the deeper soil moisture memory with longer time duration Soil moisture memory does not have obvious impacts on the phenology of woody plants

  8. SMOS validation of soil moisture and ocen salinity (SMOS) soil moisture over watershed networks in the U.S.

    Science.gov (United States)

    Estimation of soil moisture at large scale has been performed using several satellite-based passive microwave sensors and a variety of retrieval methods. The most recent source of soil moisture is the European Space Agency Soil Moisture and Ocean Salinity (SMOS) mission. A thorough validation must b...

  9. Effects of the build-in-moisture on indoor climate and wood moisture of timber mixed construction; Auswirkungen der Baurestfeuchte auf Innenklima und Holzfeuchte bei Holz-Mischbauweisen

    Energy Technology Data Exchange (ETDEWEB)

    Teibinger, Martin [Holzforschung Austria, Franz Grill Strasse 7, A-1030 Wien (Austria); Bednar, Thomas [Institut fuer Hochbau und Technologie, Zentrum fuer Bauphysik und Bauakustik, Karlsplatz 13/206, A-1030 Wien (Austria)

    2005-10-01

    Within the scope of the competence center ''wood technology'' the Holzforschung Austria deals with the combination of prefabricated timber elements in the building shell with concrete construction parts for high rise buildings. In addition to the design of construction details a one-zone model has been created - in close collaboration with the Technical University of Vienna - to analyze the effects of residual humidity on the internal climate and on the moisture content of the timber elements. The simulated drying properties of the concrete elements are consistent with the results of the analysis of the Verein der Oesterreichischen Zementfabrikanten in matters of drying time and change of moisture content. In addition to the variation of the beginning and progress of construction work and the behavior of air conditioning three different exterior wall constructions - one timber frame construction with OSB and one with PE as vapour barrier and a construction with solid timber boards without vapour barrier have been analysed. (Abstract Copyright [2005], Wiley Periodicals, Inc.) [German] Im Rahmen des Kompetenzzentrums ''Holztechnologie'' beschaeftigt sich die Holzforschung Austria mit den Kombinationsmoeglichkeiten von hochwaermegedaemmten Holzelementen in der Gebaeudehuelle mit einer mineralischen Tragstruktur fuer den urbanen Wohnungsbau. Neben der Entwicklung von Anschlussdetails wurde u. a. in Zusammenarbeit mit der Technischen Universitaet Wien ein Modell zur Untersuchung des Einflusses der Baurestfeuchte auf die Holzelemente entwickelt. Das simulierte Trocknungsverhalten der mineralischen Bauteile stimmt sowohl hinsichtlich Trocknungszeiten als auch hinsichtlich Feuchteabgabe mit den Untersuchungen des Vereins der Oesterreichischen Zementfabrikanten ueberein. Neben der Variation des Baubeginns, des Baufortschrittes und des Lueftungsverhaltens wurden als Aussenwandelemente Holzrahmenkonstruktionen mit einer OSB

  10. Soil moisture memory at sub-monthly time scales

    Science.gov (United States)

    Mccoll, K. A.; Entekhabi, D.

    2017-12-01

    For soil moisture-climate feedbacks to occur, the soil moisture storage must have `memory' of past atmospheric anomalies. Quantifying soil moisture memory is, therefore, essential for mapping and characterizing land-atmosphere interactions globally. Most previous studies estimate soil moisture memory using metrics based on the autocorrelation function of the soil moisture time series (e.g., the e-folding autocorrelation time scale). This approach was first justified by Delworth and Manabe (1988) on the assumption that monthly soil moisture time series can be modelled as red noise. While this is a reasonable model for monthly soil moisture averages, at sub-monthly scales, the model is insufficient due to the highly non-Gaussian behavior of the precipitation forcing. Recent studies have shown that significant soil moisture-climate feedbacks appear to occur at sub-monthly time scales. Therefore, alternative metrics are required for defining and estimating soil moisture memory at these shorter time scales. In this study, we introduce metrics, based on the positive and negative increments of the soil moisture time series, that can be used to estimate soil moisture memory at sub-monthly time scales. The positive increments metric corresponds to a rapid drainage time scale. The negative increments metric represents a slower drying time scale that is most relevant to the study of land-atmosphere interactions. We show that autocorrelation-based metrics mix the two time scales, confounding physical interpretation. The new metrics are used to estimate soil moisture memory at sub-monthly scales from in-situ and satellite observations of soil moisture. Reference: Delworth, Thomas L., and Syukuro Manabe. "The Influence of Potential Evaporation on the Variabilities of Simulated Soil Wetness and Climate." Journal of Climate 1, no. 5 (May 1, 1988): 523-47. doi:10.1175/1520-0442(1988)0012.0.CO;2.

  11. Moisture relationships in composting processes

    NARCIS (Netherlands)

    Richard, T.L.; Veeken, A.H.M.

    2002-01-01

    Moisture is a key environmental factor that affects many aspects of the composting process. Biodegradation kinetics are affected by moisture through changes in oxygen diffusion, water potential and water activity, and microbial growth rates. These relationships are made more complex by the dynamic

  12. Influence of chemical treatments on moisture-induced dimensional change and elastic modulus of earlywood and latewood

    Science.gov (United States)

    Robert J. Moon; Joseph Wells; David E. Kretschmann; James Evans; Alex C. Wiedenhoeft; Charles R. Frihart

    2010-01-01

    To better understand the performance of bonded, coated, and modified wood, knowledge of how these processes alter the dimensional change and mechanical properties of wood at a given moisture content (MC) are important. These localized influences on earlywood (EW) and latewood (LW) properties are not well understood. In the present study, the influence of chemical...

  13. CPAC optical moisture monitoring: Characterization of composition and physical effects on moisture determination Task 2A report

    International Nuclear Information System (INIS)

    Veltkamp, D.J.

    1994-01-01

    The impact of particle size and chemical composition variations on determination of tank simulant moisture from near infrared (NIR) optical spectra are presented. This work shows particle size and chemical variations will impact moisture predictions from NIR spectra. However, the prediction errors can be minimized if calibration models are built with samples containing these variations as interferents. Prior work showed the NIR spectral region (1100 to 2500 nm) could be used to predict moisture content of BY-104 tank simulant with a standard error less of approximately 0.5 wt%. Particle size will increase moisture prediction error if calibration-models do not include the same particle size ranges as unknown samples. A combined particle size model with 0-420 x10 -6 m, 420-841 x 10 -6 m, and 841 x 10 -6 m-2 mm diameter particles predicted 0.59, 0.34 nd 0.23 wt% errors respectively for samples containing only these size ranges and 0.80 wt% error for a samples with all particle size ranges. Chemical composition would also increase moisture prediction error if calibration model samples chemically differ from unknown samples. For a BY-104 simulant, increases in NaOH, NaAlO 2 , Na 2 SiO 3 , and Na 3 PO 4 produced moisture predictions that were lower than the actual moisture levels while increases in FE(NO 3 ) 3 , Ca(NO 3 ) 2 , and Mg (NO 3 ) 2 resulted in a higher than actual moisture prediction. Systematic changes in the NIR spectra could be observed for these families of materials. When all of the composition variations were included in a single model, the model had a moisture prediction error of 1.41 wt% as compared to a 2.96 wt% error without model changes. This work shows a calibration model based on a single set of tightly controlled experimental conditions will tend to have somewhat larger prediction errors when applied to samples collected with variations outside of such conditions

  14. Optimising hydrogen bonding in solid wood

    DEFF Research Database (Denmark)

    Engelund, Emil Tang

    2009-01-01

    The chemical bonds of wood are both covalent bonds within the wood polymers and hydrogen bonds within and between the polymers. Both types of bonds are responsible for the coherence, strength and stiffness of the material. The hydrogen bonds are more easily modified by changes in load, moisture...... and temperature distorting the internal bonding state. A problem arises when studying hydrogen bonding in wood since matched wood specimens of the same species will have very different internal bonding states. Thus, possible changes in the bonding state due to some applied treatment such as conditioning...... maintaining 100 % moisture content of the wood. The hypothesis was that this would enable a fast stress relaxation as a result of reorganization of bonds, since moisture plasticizes the material and temperature promotes faster kinetics. Hereby, all past bond distortions caused by various moisture, temperature...

  15. Nematode survival in relation to soil moisture

    NARCIS (Netherlands)

    Simons, W.R.

    1973-01-01

    Established nematode populations are very persistent in the soil. It is known that they need sufficient soil moisture for movement, feeding and reproduction (fig. 5), and that there are adverse soil moisture conditions which they cannot survive. The influence of soil moisture on survival

  16. Assessment of SMOS Soil Moisture Retrieval Parameters Using Tau-Omega Algorithms for Soil Moisture Deficit Estimation

    Science.gov (United States)

    Srivastava, Prashant K.; Han, Dawei; Rico-Ramirez, Miguel A.; O'Neill, Peggy; Islam, Tanvir; Gupta, Manika

    2014-01-01

    Soil Moisture and Ocean Salinity (SMOS) is the latest mission which provides flow of coarse resolution soil moisture data for land applications. However, the efficient retrieval of soil moisture for hydrological applications depends on optimally choosing the soil and vegetation parameters. The first stage of this work involves the evaluation of SMOS Level 2 products and then several approaches for soil moisture retrieval from SMOS brightness temperature are performed to estimate Soil Moisture Deficit (SMD). The most widely applied algorithm i.e. Single channel algorithm (SCA), based on tau-omega is used in this study for the soil moisture retrieval. In tau-omega, the soil moisture is retrieved using the Horizontal (H) polarisation following Hallikainen dielectric model, roughness parameters, Fresnel's equation and estimated Vegetation Optical Depth (tau). The roughness parameters are empirically calibrated using the numerical optimization techniques. Further to explore the improvement in retrieval models, modifications have been incorporated in the algorithms with respect to the sources of the parameters, which include effective temperatures derived from the European Center for Medium-Range Weather Forecasts (ECMWF) downscaled using the Weather Research and Forecasting (WRF)-NOAH Land Surface Model and Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) while the s is derived from MODIS Leaf Area Index (LAI). All the evaluations are performed against SMD, which is estimated using the Probability Distributed Model following a careful calibration and validation integrated with sensitivity and uncertainty analysis. The performance obtained after all those changes indicate that SCA-H using WRF-NOAH LSM downscaled ECMWF LST produces an improved performance for SMD estimation at a catchment scale.

  17. 7 CFR 868.307 - Moisture.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Moisture. 868.307 Section 868.307 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD... Application of Standards § 868.307 Moisture. Water content in milled rice as determined by an FGIS approved...

  18. Space-time modeling of soil moisture

    Science.gov (United States)

    Chen, Zijuan; Mohanty, Binayak P.; Rodriguez-Iturbe, Ignacio

    2017-11-01

    A physically derived space-time mathematical representation of the soil moisture field is carried out via the soil moisture balance equation driven by stochastic rainfall forcing. The model incorporates spatial diffusion and in its original version, it is shown to be unable to reproduce the relative fast decay in the spatial correlation functions observed in empirical data. This decay resulting from variations in local topography as well as in local soil and vegetation conditions is well reproduced via a jitter process acting multiplicatively over the space-time soil moisture field. The jitter is a multiplicative noise acting on the soil moisture dynamics with the objective to deflate its correlation structure at small spatial scales which are not embedded in the probabilistic structure of the rainfall process that drives the dynamics. These scales of order of several meters to several hundred meters are of great importance in ecohydrologic dynamics. Properties of space-time correlation functions and spectral densities of the model with jitter are explored analytically, and the influence of the jitter parameters, reflecting variabilities of soil moisture at different spatial and temporal scales, is investigated. A case study fitting the derived model to a soil moisture dataset is presented in detail.

  19. Effect of different materials in soil on the neutron moisture gauge readings

    International Nuclear Information System (INIS)

    Abdul-Majid, S.

    1991-01-01

    Neutron moisture gauges that depend on scattering and thermalization of neutrons have been in use for a long time. The hydrogen in water is the effective element in thermalizing the neutrons coming from a neutron source, where they are detected by neutron detector such as B F 3 counter or boron lined counter. The high cross-section of boron for thermal neutrons makes detectors containing boron ideal for this application. There are always some possibility that some materials exist in soil other than water which can moderate and hence introduce false results in moisture contents measurements. For example, materials such as hydrocarbons, asphalt, wood, etc., contain both hydrogen and carbon. These elements are good neutron moderators. The effects of the existence of such materials in the soil on the gauge readings were examined. Elements of high neutron cross-section such as boron can be a source of large error as well, since they absorb thermal neutrons giving low moisture content value. The effect of such materials as part of the soil constituent on the gauge reading was also examined.3 fig

  20. Optical transparency of paper as a function of moisture content with applications to moisture measurement.

    Science.gov (United States)

    Forughi, A F; Green, S I; Stoeber, B

    2016-02-01

    Accurate measurement of the moisture content of paper is essential in papermaking and is also important in some paper-based microfluidic devices. Traditional measurement techniques provide very limited spatiotemporal resolution and working range. This article presents a novel method for moisture content measurement whose operating principle is the strong correlation between the optical transparency of paper and its moisture content. Spectrographic and microscopic measurement techniques were employed to characterize the relation of moisture content and relative transparency of four types of paper: hardwood chemi-thermomechanical pulp paper, Northern bleached softwood kraft paper, unbleached softwood kraft paper, and General Electric(®) Whatman™ grade 1 chromatography paper. It was found that for all paper types, the paper transparency increased monotonically with the moisture content (as the ratio of the mass-of-water to the mass-of-dry-paper increased from 0% to 120%). This significant increase in relative transparency occurred due to the refractive index matching role of water in wet paper. It is further shown that mechanical loading of the paper has little impact on the relative transparency, for loadings that would be typical on a paper machine. The results of two transient water absorption experiments are presented that show the utility and accuracy of the technique.

  1. Measuring the Moisture Content of Green Wood Using Time Domain Reflectometry

    Science.gov (United States)

    Laurence Schimleck; Kim Love-Myers; Joe Sanders; Heath Raybon; Richard Daniels; Jerry Mahon; Edward Andrews; Erik Schilling

    2011-01-01

    The responsible usage of water by facilities that rely on wet log storage in the southern United States has become an issue of great importance as restrictions on water usage have grown in recent years. In order to learn about the dynamics of moisture content in wet-stored logs over time, it is necessary to conduct continuous monitoring of log piles. Time domain...

  2. 7 CFR 51.2561 - Average moisture content.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Average moisture content. 51.2561 Section 51.2561... STANDARDS) United States Standards for Grades of Shelled Pistachio Nuts § 51.2561 Average moisture content. (a) Determining average moisture content of the lot is not a requirement of the grades, except when...

  3. Moisture Management for High R-Value Walls

    Energy Technology Data Exchange (ETDEWEB)

    Lepage, R. [Building Science Corporation, Somerville, MA (United States); Schumacher, C. [Building Science Corporation, Somerville, MA (United States); Lukachko, A. [Building Science Corporation, Somerville, MA (United States)

    2013-11-01

    This report explains the moisture-related concerns for high R-value wall assemblies and discusses past Building America research work that informs this study. In this project, hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones. The modeling program assessed the moisture durability of the wall assemblies based on three primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage; the report presents results of the study.

  4. Moisture monitoring and control system engineering study

    International Nuclear Information System (INIS)

    Carpenter, K.E.; Fadeff, J.G.

    1995-01-01

    During the past 50 years, a wide variety of chemical compounds have been placed in the 149 single-shell tanks (SSTS) on the Hanford Site. A concern relating to chemical stability, chemical control, and safe storage of the waste is the potential for propagating reactions as a result of ferrocyanide-oxidizer and organic-oxidizer concentrations in the SSTS. Propagating reactions in fuel-nitrate mixtures are precluded if the amounts of fuel and moisture present in the waste are within specified limits. Because most credible ignition sources occur near the waste surface, the main emphasis of this study is toward monitoring and controlling moisture in the top 14 cm (5.5 in.) of waste. The purpose of this engineering study is to recommend a moisture monitoring and control system for use in SSTs containing sludge and saltcake. This study includes recommendations for: (1) monitoring and controlling moisture in SSTs; (2) the fundamental design criteria for a moisture monitoring and control system; and (3) criteria for the deployment of a moisture monitoring and control system in hanford Site SSTs. To support system recommendations, technical bases for selecting and using a moisture monitoring and control system are presented. Key functional requirements and a conceptual design are included to enhance system development and establish design criteria

  5. Skin moisturization mechanisms: new data.

    Science.gov (United States)

    Bonté, F

    2011-05-01

    The main function of the skin is to protect the body against exogenous substances and excessive water loss. The skin barrier is located in the outermost layer of the skin, called the stratum corneum, which is composed of corneocytes, originating from the keratinocytes differentiation process, embedded in organized complex lipid domains. Moisturizing of the skin is recognized as the first anti-aging skin care. Skin moisturization is essential for its appearance, protection, complexion, softness and the reinforcement of its barrier properties against deleterious and exogenous environmental factors. The intrinsic water binding capacity of skin is not only due to the complex natural moisturizing factor present in corneocytes, but also to hyaluronic acid and a regulated water transport within the skin. Recent data shows that the water movements between the cells at the different levels of the epidermis are due to dedicated water and glycerol transport proteins named aquaporins. Their role in the skin moisturization is completed by corneodesmosomes and tight junctions. Water and pH are now shown to be of prime importance in the regulation of the epidermal enzymes linked to corneocytes desquamation and lipid synthesis. Furthermore, the level of moisturization of the skin is important in its protection against repeated exposure to various irritant agents or phenomena such as very frequent washing with strong tensioactive materials. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  6. Quality Assurance of Rice and Paddy Moisture Measurements in Thailand

    Science.gov (United States)

    Sinhaneti, T.; Keawprasert, T.; Puuntharo, P.; Triarun, W.

    2017-10-01

    A bilateral comparison in moisture measurement between the National Institute of Metrology Thailand (NIMT) and the Central Bureau of Weights and Measures (CBWM) was organized for quality assuring of rice and paddy moisture measurement in Thailand. The bilateral comparison was conducted by using the same batch of sample and moisture meter as transfer device. It consisted of two parts: moisture measurement in rice and in paddy. A rice moisture meter belonging to CBWM and rice standards prepared at the nominal moisture content of 10 %, 12 %, 14 % and 16 % at NIMT, were used for rice moisture comparison, while a paddy moisture meter belonging to NIMT and paddy standards prepared at the nominal moisture content of 12 %, 14 %, 16 % and 18 % at CBWM, were used for paddy moisture comparison. Both laboratories measured the moisture content of a sample by using the standard method in ISO 712 and used that sample to calibrate a moisture meter by means of the method based on ISO 7700-1. Since the moisture content of the sample can change during the comparison, correction values in moisture content between the standard value and the reading value from the moisture meter are used as calibration results for the comparison evaluation. For the rice moisture comparison, differences in the correction value measured by the two laboratories vary from 0.18 % to 0.46 %, with their combined comparison uncertainty of 0.37 % (k= 2). The main contribution to the difference comes from the standard values from both laboratories differing from 0.27 % to 0.53 %, as the rice standard was found to drift in moisture content less than 0.05 %. Similarly to the rice moisture comparison, differences in the correction value for the paddy moisture measurement range from 0.08 % to 0.56 % with the combined comparison uncertainty of 0.38 % (k = 2), whereas the stability in moisture content of the paddy sample at NIMT was found to be within 0.12 %.

  7. Use of midlatitude soil moisture and meteorological observations to validate soil moisture simulations with biosphere and bucket models

    Science.gov (United States)

    Robock, Alan; Vinnikov, Konstantin YA.; Schlosser, C. Adam; Speranskaya, Nina A.; Xue, Yongkang

    1995-01-01

    Soil moisture observations in sites with natural vegetation were made for several decades in the former Soviet Union at hundreds of stations. In this paper, the authors use data from six of these stations from different climatic regimes, along with ancillary meteorological and actinometric data, to demonstrate a method to validate soil moisture simulations with biosphere and bucket models. Some early and current general circulation models (GCMs) use bucket models for soil hydrology calculations. More recently, the Simple Biosphere Model (SiB) was developed to incorporate the effects of vegetation on fluxes of moisture, momentum, and energy at the earth's surface into soil hydrology models. Until now, the bucket and SiB have been verified by comparison with actual soil moisture data only on a limited basis. In this study, a Simplified SiB (SSiB) soil hydrology model and a 15-cm bucket model are forced by observed meteorological and actinometric data every 3 h for 6-yr simulations at the six stations. The model calculations of soil moisture are compared to observations of soil moisture, literally 'ground truth,' snow cover, surface albedo, and net radiation, and with each other. For three of the stations, the SSiB and 15-cm bucket models produce good simulations of seasonal cycles and interannual variations of soil moisture. For the other three stations, there are large errors in the simulations by both models. Inconsistencies in specification of field capacity may be partly responsible. There is no evidence that the SSiB simulations are superior in simulating soil moisture variations. In fact, the models are quite similar since SSiB implicitly has a bucket embedded in it. One of the main differences between the models is in the treatment of runoff due to melting snow in the spring -- SSiB incorrectly puts all the snowmelt into runoff. While producing similar soil moisture simulations, the models produce very different surface latent and sensible heat fluxes, which

  8. Simple grain moisture content determination from microwave measurements

    International Nuclear Information System (INIS)

    Kraszewski, A.W.; Trabelsi, S.; Nelson, S.O.

    1998-01-01

    Moisture content of wheat, Triticum aestivum L., is expressed as a function of the ratio of microwave attenuation and phase shift, measured at 16.8 GHz, and grain temperature. Validation of the calibration equation indicated that moisture content was obtained with an uncertainty less than +/- 0.45% moisture at the 95% confidence level, independent of density variation, at temperatures from -1 degree C to 42 degrees C, and moisture contents from 10% to 19%. Moisture determination does not depend on the layer thickness of the wheat norits bulk density. No differences between two wheat cultivars were observed in the measurement data

  9. Heat and Moisture transport of socks

    Science.gov (United States)

    Komárková, P.; Glombíková, V.; Havelka, A.

    2017-10-01

    Investigating the liquid moisture transport and thermal properties is essential for understanding physiological comfort of clothes. This study reports on an experimental investigation of moisture management transport and thermal transport on the physiological comfort of commercially available socks. There are subjective evaluation and objective measurements. Subjective evaluation of the physiological comfort of socks is based on individual sensory perception of probands during and after physical exertion. Objective measurements were performed according to standardized methods using Moisture Management tester for measuring the humidity parameters and C-term TCi analyzer for thermal conductivity and thermal effusivity. The obtained values of liquid moisture transport and thermal properties were related to the material composition and structure of the tested socks. In summary, these results show that objective measurement corresponds with probands feelings.

  10. Moisture sorption isotherms of dehydrated whey proteins

    Directory of Open Access Journals (Sweden)

    Suzana Rimac Brnčić

    2010-03-01

    Full Text Available Moisture sorption isotherms describe the relation between the moisture content of the dry material (food and relative humidity of the surrounding environment. The data obtained are important in modelling of drying process conditions, packaging and shelf-life stability of food that will provide maximum retaining of aroma, colour and texture as well as nutritive and biological value. The objective of this research was to establish the equilibrium moisture content and water activity, as well as monolayer value of two commercial powdered whey protein isolates before and after tribomechanical micronisation and enzymatic hydrolysis, respectively. At the same time it was necessary to evaluate the best moisture sorption isotherm equation to fit the experimental data. The equilibrium moisture contents in investigated samples were determined using standard gravimetric method at 20 °C. The range of water activities was 0.11 to 0.75. The monolayer moisture content was estimated from sorption data using Brunauer-Emmett-Teller (BET and Guggenheim-Anderson-de Boer (GAB models. The results have shown that tribomechanically treated whey protein isolates as well as protein hydrolizates had lower monolayer moisture content values as well as higher corresponding water activity. Therefore, in spite of the fact that they have lower moisture content, they can be storage at higher relative humidity compared to untreated samples. BET model gave better fit to experimental sorption data for a water activity range from 0.11-0.54, while GAB model gave the closest fit for a water activity to 0.75.

  11. Investigating soil moisture-climate interactions with prescribed soil moisture experiments: an assessment with the Community Earth System Model (version 1.2)

    Science.gov (United States)

    Hauser, Mathias; Orth, René; Seneviratne, Sonia I.

    2017-04-01

    Land surface hydrology is an important control of surface weather and climate. A valuable technique to investigate this link is the prescription of soil moisture in land surface models, which leads to a decoupling of the atmosphere and land processes. Diverse approaches to prescribe soil moisture, as well as different prescribed soil moisture conditions have been used in previous studies. Here, we compare and assess four methodologies to prescribe soil moisture and investigate the impact of two different estimates of the climatological seasonal cycle used to prescribe soil moisture. Our analysis shows that, though in appearance similar, the different approaches require substantially different long-term moisture inputs and lead to different temperature signals. The smallest influence on temperature and the water balance is found when prescribing the median seasonal cycle of deep soil liquid water, whereas the strongest signal is found when prescribing soil liquid and soil ice using the mean seasonal cycle. These results indicate that induced net water-balance perturbations in experiments investigating soil moisture-climate coupling are important contributors to the climate response, in addition to the intended impact of the decoupling. These results help to guide the set-up of future experiments prescribing soil moisture, as for instance planned within the Land Surface, Snow and Soil Moisture Model Intercomparison Project (LS3MIP).

  12. Moisture Sorption in Porous Materials

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    2007-01-01

    pressure and weight data can be "translated" to pore geometry by known physical relationships. In this context, analytical descriptions are important which can relate moisture condensation in pore structures to ambient vapor pressure. Such a description, the extended BET-relation, is presented...... physical parameters, the so-called BET-parameters: The heat property factor, C, and the pore surface, SBET (derived from the so-called uni-molecular moisture content uBET). A software ‘SORP07’ has been developed to handle any calculations made in the paper. For readers who have a special interest...... in the subject considered this software is available on request to the author. Keywords: Porous materials, moisture, adsorption, desorption, BET-parameters....

  13. Moisture Dependence of physical Properties and Specific Heat Capacity of Neem (Azadirachta Indica A. Juss Kernels

    Directory of Open Access Journals (Sweden)

    A. Dauda

    2017-02-01

    Full Text Available This study investigated the effect of moisture content on the physical properties and specific heat capacity of Neem (Azadirachta Indica A. Juss nut kernels. The major, intermediate and minor axial dimensions of the kernels increased from 1.04 to 1.23cm, 0.42 to 0.6cm, and 0.32 to 0.45cm respectively, as the moisture content increased from 5.2 to 44.9 % (db. The arithmetic and geometric mean diameters determined at the same moisture level were significantly different from each other, with the arithmetic mean diameter being higher. In the above moisture range, one thousand kernel weight, true density, porosity, sphericity, roundness and surface area all increased linearly from 0.0987 to 0.1755kg, 632 to 733kgm-3, 6.42 to 32.14%, 41.3 to 47.5%, 22 to 36% and 13 to 24cm2 respectively, while bulk density decreased from 591.4 to 497.4kgm-3 with increase in moisture content. Angle of repose increased from 21.22 to 29.8o with increase in moisture content. The Static coefficient of friction on ply wood with grains parallel to the direction of movement ranged from 0.41 to 0.61, it ranged from 0.19 to 0.24 on on fiber glass, 0.28 to .038 on hessian bag material and 0.25 to 0.33 on galvanized steel sheet. The specific heat of the seed varied from 2738.1- 4345.4J/kg/oC in the above moisture range.

  14. Study on the optimal moisture adding rate of brown rice during germination by using segmented moisture conditioning method.

    Science.gov (United States)

    Cao, Yinping; Jia, Fuguo; Han, Yanlong; Liu, Yang; Zhang, Qiang

    2015-10-01

    The aim of this study was to find out the optimal moisture adding rate of brown rice during the process of germination. The process of water addition in brown rice could be divided into three stages according to different water absorption speeds in soaking process. Water was added with three different speeds in three stages to get the optimal water adding rate in the whole process of germination. Thus, the technology of segmented moisture conditioning which is a method of adding water gradually was put forward. Germinated brown rice was produced by using segmented moisture conditioning method to reduce the loss of water-soluble nutrients and was beneficial to the accumulation of gamma aminobutyric acid. The effects of once moisture adding amount in three stages on the gamma aminobutyric acid content in germinated brown rice and germination rate of brown rice were investigated by using response surface methodology. The optimum process parameters were obtained as follows: once moisture adding amount of stage I with 1.06 %/h, once moisture adding amount of stage II with 1.42 %/h and once moisture adding amount of stage III with 1.31 %/h. The germination rate under the optimum parameters was 91.33 %, which was 7.45 % higher than that of germinated brown rice produced by soaking method (84.97 %). The content of gamma aminobutyric acid in germinated brown rice under the optimum parameters was 29.03 mg/100 g, which was more than two times higher than that of germinated brown rice produced by soaking method (12.81 mg/100 g). The technology of segmented moisture conditioning has potential applications for studying many other cereals.

  15. Effective moisture diffusivity, moisture sorption, thermo-physical properties and infrared drying kinetics of germinated paddy

    Directory of Open Access Journals (Sweden)

    Supawan Tirawanichakul

    2014-02-01

    Full Text Available Temperature and relative humidity (RH dependence of moisture sorption phenomena for agricultural products provide valuable information related to the thermodynamics of the system. So the equilibrium moisture contents (EMC, effective moisture diffusivity (Deff and thermo-physical properties in terms of void fraction, specific heat capacity, and the apparent density of germinated non-waxy Suphanburi 1 paddy were evaluated. Five commonly cited EMC equations were fitted to the experimental data among temperatures of 40-60°C correlating with RH of 0-90%. The results showed that the modified GAB equation was the best function for describing experimental results while those evaluated thermo-physical properties depended on moisture content. To determine drying kinetics model, the simulated values using Midilli et al. (2002 model and Page’s model was the best fitting to exact drying kinetics values for infrared (IR and hot air (HA drying, respectively. Finally, the Deff value of paddy dried with IR and HA sources were also evaluated and the calculated Deff value of both HA and IR drying was in order of 10-9 m2/s.

  16. Structure of the urban moisture field

    International Nuclear Information System (INIS)

    Sisterson, D.L.; Dirks, R.A.

    1975-01-01

    In the 26 July 1974 case study in St. Louis as a part of Project METROMEX, aircraft and surface network stations were used to determine specific humidity and potential temperature patterns near the surface and at two levels within the mixing layer. From the data acquired at these three levels, three-dimensional analyses of the moisture fields in the mixing layer were constructed. The mesoscale dry regions observed throughout the mixing layer correspond to the more impervious surfaces of the urban area. From energy budget considerations, latent heat fluxes are small over these impervious surfaces owing to the large runoff of precipitation and the lack of moisture retention capabilities. Hence, urbanization obviously alters the local energy budget. Surface boundary layer conditions are determined by heat and moisture fluxes. A new internal boundary layer within the city is formed after the breakdown of the radiation inversion in order to compensate for the alteration of sensible heat and latent heat energies. Hence, isolated semistagnant urban air is replenished by moisture only as quickly as evapotranspiration from impervious surfaces will allow. The city surface, therefore, is not a sink of moisture, but rather a reduced source relative to rural areas

  17. Moisture Transfer in Ventilated Facade Structures

    Directory of Open Access Journals (Sweden)

    Olshevskyi Vyacheslav

    2016-01-01

    Full Text Available This article discusses the phenomenon of moisture transfer in the designs of ventilated facades (VF. The main ways of moisture transfer are defined. The negative factors connected with moisture accumulation and excessive moistening of insulation are given. The physical processes occurring in the gap of the building envelope due to saturation of air with water vapor are described. The dependence of the intensity of the mass transfer on the air velocity in the layer is considered. Much attention is paid to the selection of the optimum design of the facade, namely a system with or without grooved lines. The dependence of velocity and temperature on the width of the ventilated gap is established empirically for the constructions with open and closed grooves. Expediency of a design without grooves to effectively remove moisture is determined.

  18. Drying and control of moisture content and dimensional changes

    Science.gov (United States)

    Richard Bergman

    2010-01-01

    The discussion in this chapter is concerned with moisture content determination, recommended moisture content values, drying methods, methods of calculating dimensional changes, design factors affecting such changes in structures, and moisture content control during transit, storage, and construction. Data on green moisture content, fiber saturation point, shrinkage,...

  19. Digital neutron moisture meter for moisture determination in the cokes and building materials

    International Nuclear Information System (INIS)

    Chibovski, R.; Igel'ski, A.; Kiyanya, K.; Kiyanya, S.; Mnikh, Eh.; Sledzevski, R.; Verba, V.

    1979-01-01

    Description is given of the digital neutron moisture gage for measuring water content in coke or in dry building materials. The device can work independently with indication of the results to personnel carrying out control operation and adjustment of the process or as a part of an automated control system with supplying the results of measurements in a form of analogous signals or electric pulses in the preselected code. The moisture gage described consists of two units: measuring probes with containers and the desk with power supply and the system for digital processing of a radiometric signal. The measuring probe consists of the asotopic fast neutrons source; helium proportional counter of slow neutrons and a pulse amplifier. The probe is mounted in the bunker with the material measured and is located inside the protective tube made of the weare-resistant material. To obtain high accuracy of measurements and to obtain the measuring instrument's reading immediately in the units of moisture measurement, the digizal converter circuit for radiometric signals processing is used. The The digital converter circuit cited, can be applied to any calibration dependence of linear type with initial value. The block diagram of the device is given. The device described permits to measure the moisture content in the metallurgy coks and in the building materials in one minute and with the error not more than 0.5% [ru

  20. Passive microwave remote sensing of soil moisture

    International Nuclear Information System (INIS)

    Jackson, T.J.; Schmugge, T.J.

    1986-01-01

    Microwave remote sensing provides a unique capability for direct observation of soil moisture. Remote measurements from space afford the possibility of obtaining frequent, global sampling of soil moisture over a large fraction of the Earth's land surface. Microwave measurements have the benefit of being largely unaffected by cloud cover and variable surface solar illumination, but accurate soil moisture estimates are limited to regions that have either bare soil or low to moderate amounts of vegetation cover. A particular advantage of passive microwave sensors is that in the absence of significant vegetation cover soil moisture is the dominant effect on the received signal. The spatial resolutions of passive microwave soil moisture sensors currently considered for space operation are in the range 10–20 km. The most useful frequency range for soil moisture sensing is 1–5 GHz. System design considerations include optimum choice of frequencies, polarizations, and scanning configurations, based on trade-offs between requirements for high vegetation penetration capability, freedom from electromagnetic interference, manageable antenna size and complexity, and the requirement that a sufficient number of information channels be available to correct for perturbing geophysical effects. This paper outlines the basic principles of the passive microwave technique for soil moisture sensing, and reviews briefly the status of current retrieval methods. Particularly promising are methods for optimally assimilating passive microwave data into hydrologic models. Further studies are needed to investigate the effects on microwave observations of within-footprint spatial heterogeneity of vegetation cover and subsurface soil characteristics, and to assess the limitations imposed by heterogeneity on the retrievability of large-scale soil moisture information from remote observations

  1. Analysis of soil moisture memory from observations in Europe

    Science.gov (United States)

    Orth, R.; Seneviratne, S. I.

    2012-08-01

    Soil moisture is known to show distinctive persistence characteristics compared to other quantities in the climate system. As soil moisture is governing land-atmosphere feedbacks to a large extent, its persistence can provide potential to improve seasonal climate predictions. So far, many modeling studies have investigated the nature of soil moisture memory, with consistent, but model-dependent results. This study investigates soil moisture memory in long-term observational records based on data from five stations across Europe. We investigate spatial and seasonal variations in soil moisture memory and identify their main climatic drivers. Also, we test an existing framework and introduce an extension thereof to approximate soil moisture memory and evaluate the contributions of its driving processes. At the analyzed five sites, we identify the variability of initial soil moisture divided by that of the accumulated forcing over the considered time frame as a main driver of soil moisture memory that reflects the impact of the precipitation regime and of soil and vegetation characteristics. Another important driver is found to be the correlation of initial soil moisture with subsequent forcing that captures forcing memory as it propagates to the soil and also land-atmosphere interactions. Thereby, the role of precipitation is found to be dominant for the forcing. In contrast to results from previous modeling studies, the runoff and evapotranspiration sensitivities to soil moisture are found to have only a minor influence on soil moisture persistence at the analyzed sites. For the central European sites, the seasonal cycles of soil moisture memory display a maximum in late summer and a minimum in spring. An opposite seasonal cycle is found at the analyzed site in Italy. High soil moisture memory is shown to last up to 40 days in some seasons at most sites. Extremely dry or wet states of the soil tend to increase soil moisture memory, suggesting enhanced prediction

  2. Design of Moisture Content Detection System

    Science.gov (United States)

    Wang, W. C.; Wang, L.

    In this paper, a method for measuring the moisture content of grain was presented based on single chip microcomputer and capacitive sensor. The working principle of measuring moisture content is introduced and a concentric cylinder type of capacitive sensor is designed, the signal processing circuits of system are described in details. System is tested in practice and discussions are made on the various factors affecting the capacitive measuring of grain moisture based on the practical experiments, experiment results showed that the system has high measuring accuracy and good controlling capacity.

  3. Soil moisture content with global warming

    International Nuclear Information System (INIS)

    Vinnikov, K.Ya.

    1990-01-01

    The potential greenhouse-gas-induced changes in soil moisture, particularly the desiccation of the Northern Hemisphere contents in summer, are discussed. To check the conclusions based on climate models the authors have used long-term measurements of contemporary soil moisture in the USSR and reconstructions of soil moisture for the last two epochs that were warmer than the present, namely, the Holocene optimum, 5,000-6,000 years ago, and the last interglacial, about 125,000 years ago. The analysis shows that there is a considerable disagreement between the model results and the empirical data

  4. Effects of heat-moisture treatment reaction conditions on the physicochemical and structural properties of maize starch: moisture and length of heating.

    Science.gov (United States)

    Sui, Zhongquan; Yao, Tianming; Zhao, Yue; Ye, Xiaoting; Kong, Xiangli; Ai, Lianzhong

    2015-04-15

    Changes in the properties of normal maize starch (NMS) and waxy maize starch (WMS) after heat-moisture treatment (HMT) under various reaction conditions were investigated. NMS and WMS were adjusted to moisture levels of 20%, 25% and 30% and heated at 100 °C for 2, 4, 8 and 16 h. The results showed that moisture content was the most important factor in determining pasting properties for NMS, whereas the heating length was more important for WMS. Swelling power decreased in NMS but increased in WMS, and while the solubility index decreased for both samples, the changes were largely determined by moisture content. The gelatinisation temperatures of both samples increased with increasing moisture content but remained unchanged with increasing heating length. The Fourier transform infrared (FT-IR) absorbance ratio was affected to different extents by the moisture levels but remained constant with increasing the heating length. The X-ray intensities increased but relative crystallinity decreased to a greater extent with increasing moisture content. This study showed that the levels of moisture content and length of heating had significant impacts on the structural and physicochemical properties of normal and waxy maize starches but to different extents. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Neutron moisture measurement in materials

    International Nuclear Information System (INIS)

    Thony, J.L.

    1985-01-01

    This method is generally used for soil moisture determination but also for moisture in building materials. After a review of neutron interaction with matter (elastic and inelastic scattering, radiative capture and absorption with emission of charged particles) and of the equipment (source, detector and counting), gravimetric and chemical calibration are described and accuracy of measurement is discussed. 5 refs [fr

  6. Propagation of soil moisture memory into the climate system

    Science.gov (United States)

    Orth, R.; Seneviratne, S. I.

    2012-04-01

    Soil moisture is known for its integrative behaviour and resulting memory characteristics. Associated anomalies can persist for weeks or even months into the future, making initial soil moisture an important potential component in weather forecasting. This is particularly crucial given the role of soil moisture for land-atmosphere interactions and its impacts on the water and energy balances on continents. We present here an analysis of the characteristics of soil moisture memory and of its propagation into runoff and evapotranspiration in Europe, based on available measurements from several sites across the continent and expanding a previous analysis focused on soil moisture [1]. We identify the main drivers of soil moisture memory at the analysed sites, as well as their role for the propagation of soil moisture persistence into runoff and evapotranspiration memory characteristics. We focus on temporal and spatial variations in these relationships and identify seasonal and latitudinal differences in the persistence of soil moisture, evapotranspiration and runoff. Finally, we assess the role of these persistence characteristics for the development of agricultural and hydrological droughts. [1] Orth and Seneviratne: Analysis of soil moisture memory from observations in Europe; submitted to J. Geophysical Research.

  7. 40 CFR 75.37 - Missing data procedures for moisture.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Missing data procedures for moisture... data procedures for moisture. (a) The owner or operator of a unit with a continuous moisture monitoring system shall substitute for missing moisture data using the procedures of this section. (b) Where no...

  8. Sources of Sahelian-Sudan moisture: Insights from a moisture-tracing atmospheric model

    Science.gov (United States)

    Salih, Abubakr A. M.; Zhang, Qiong; Pausata, Francesco S. R.; Tjernström, Michael

    2016-07-01

    The summer rainfall across Sahelian-Sudan is one of the main sources of water for agriculture, human, and animal needs. However, the rainfall is characterized by large interannual variability, which has attracted extensive scientific efforts to understand it. This study attempts to identify the source regions that contribute to the Sahelian-Sudan moisture budget during July through September. We have used an atmospheric general circulation model with an embedded moisture-tracing module (Community Atmosphere Model version 3), forced by observed (1979-2013) sea-surface temperatures. The result suggests that about 40% of the moisture comes with the moisture flow associated with the seasonal migration of the Intertropical Convergence Zone (ITCZ) and originates from Guinea Coast, central Africa, and the Western Sahel. The Mediterranean Sea, Arabian Peninsula, and South Indian Ocean regions account for 10.2%, 8.1%, and 6.4%, respectively. Local evaporation and the rest of the globe supply the region with 20.3% and 13.2%, respectively. We also compared the result from this study to a previous analysis that used the Lagrangian model FLEXPART forced by ERA-Interim. The two approaches differ when comparing individual regions, but are in better agreement when neighboring regions of similar atmospheric flow features are grouped together. Interannual variability with the rainfall over the region is highly correlated with contributions from regions that are associated with the ITCZ movement, which is in turn linked to the Atlantic Multidecadal Oscillation. Our result is expected to provide insights for the effort on seasonal forecasting of the rainy season over Sahelian Sudan.

  9. Free-Tropospheric Moisture Convergence and Tropical Convective Regimes

    Science.gov (United States)

    Masunaga, H.

    2014-12-01

    It is known that quiescent periods with only shallow cumuli prevalent are frequently observed even in the deep Tropics, which is considered from the climatological perspectives as an area harboring vigorous deep convection. It is argued in this work that the free-tropospheric (FT) moisture convergence is a crucial factor for separating the stable maintenance of isolated shallow cumuli in the quiescent periods from the self-sustaining growth of organized convective systems in the dynamic periods over tropical oceans. The analysis is based on a variety of satellite measurements including Aqua AIRS T and q soundings and QuikSCAT surface wind, composited with reference to the time before or after the occurrence of precipitating clouds detected by TRMM PR. The FT moisture convergence and updraft moisture flux at cloud base are then derived from this dataset under large-scale moisture budget constraint (see Figure). Free-tropospheric precipitation efficiency (FTPE), or the ratio of precipitation to updraft moisture flux at cloud base, is introduced as a measure of convective intensity (rather than the population) over the large-scale domain. The following hypothesis is discussed in light of the analysis results. Isolated shallow cumuli would stay shallow when large-scale FT moisture is diverging (although moisture is weakly converging when integrated over the whole troposphere) since an increase in cumulus population would be counteracted by an additional moisture divergence in the FT. When large-scale FT convergence is positive, in contrast, developing clouds would induce a more moisture input and allow an unstable growth to a highly organized convective system. Zero FT moisture convergence may serve as the neutrality separating the negative feedback acting in the quiescent regime from the positive feedback instrumental for the dynamic regime.

  10. Guidelines on the prevention of built-in moisture

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Møller, Eva B.

    2014-01-01

    As a result of built-in-moisture, a number of buildings in Denmark were attacked by moulds even before the users moved in. Therefore, the Danish Building Regulations have since 2008 stipulated that building structures and materials must not, on moving in, have a moisture content that is liable...... the execution phase and the building’s capacity to withstand moisture. It also specifies how moisture should be dealt with in the general quality assurance system of the building industry. The Danish guideline is compared with similar guidelines and tools in other Nordic countries. The education of moisture...... specialists is emphasised and it is questioned whether a voluntary guideline will have the desired effect....

  11. Moisture Buffer Value of Building Materials

    DEFF Research Database (Denmark)

    Rode, Carsten; Peuhkuri, Ruut; Time, Berit

    2007-01-01

    When building materials are in contact with indoor air they have some effect to moderate the variations of indoor humidity in occupied buildings. But so far there has been a lack of a standardized quantity to characterize the moisture buffering capability of materials. It has been the objective o...... is a test protocol which expresses how materials should be tested for determination of their Moisture Buffer Value. Finally, the paper presents some of the results of a Round Robin Test on various typical building materials that has been carried out in the project....... of a recent Nordic project to define such a quantity, and to declare it in the form of a NORDTEST method. The Moisture Buffer Value is the figure that has been developed in the project as a way to appraise the moisture buffer effect of materials, and the value is described in the paper. Also explained...

  12. Moisture sorption of Thai red curry powder

    Directory of Open Access Journals (Sweden)

    Sudathip Inchuen

    2009-12-01

    Full Text Available Moisture sorption study was conducted on Thai red curry powder prepared by two different drying methods, viz. microwave and hot-air drying. Moisture sorption isotherms of the red curry powder at 30 C and water activity in the range of 0.113-0.970 were determined by a static gravimetric method. The isotherms exhibited Type III behaviour. The moisture sorption data were fitted to several sorption models and a non-linear regression analysis method was used to evaluate the constants of the sorption equations. The fit was evaluated using the coefficient of determination (R2, the reduced chi-square (2 and the root mean square error (RMSE. The GAB model followed by the Lewiski-3 model gave the best fit to the experimental data. The monolayer moisture content, taken as the safe minimum moisture level in the red curry powder, was determined using the BET equation and was found to range between 0.080 - 0.085 gram water per gram dry matter.

  13. COSMOS: the COsmic-ray Soil Moisture Observing System

    Directory of Open Access Journals (Sweden)

    M. Zreda

    2012-11-01

    Full Text Available The newly-developed cosmic-ray method for measuring area-average soil moisture at the hectometer horizontal scale is being implemented in the COsmic-ray Soil Moisture Observing System (or the COSMOS. The stationary cosmic-ray soil moisture probe measures the neutrons that are generated by cosmic rays within air and soil and other materials, moderated by mainly hydrogen atoms located primarily in soil water, and emitted to the atmosphere where they mix instantaneously at a scale of hundreds of meters and whose density is inversely correlated with soil moisture. The COSMOS has already deployed more than 50 of the eventual 500 cosmic-ray probes, distributed mainly in the USA, each generating a time series of average soil moisture over its horizontal footprint, with similar networks coming into existence around the world. This paper is written to serve a community need to better understand this novel method and the COSMOS project. We describe the cosmic-ray soil moisture measurement method, the instrument and its calibration, the design, data processing and dissemination used in the COSMOS project, and give example time series of soil moisture obtained from COSMOS probes.

  14. Spatio-temporal Root Zone Soil Moisture Estimation for Indo - Gangetic Basin from Satellite Derived (AMSR-2 and SMOS) Surface Soil Moisture

    Science.gov (United States)

    Sure, A.; Dikshit, O.

    2017-12-01

    Root zone soil moisture (RZSM) is an important element in hydrology and agriculture. The estimation of RZSM provides insight in selecting the appropriate crops for specific soil conditions (soil type, bulk density, etc.). RZSM governs various vadose zone phenomena and subsequently affects the groundwater processes. With various satellite sensors dedicated to estimating surface soil moisture at different spatial and temporal resolutions, estimation of soil moisture at root zone level for Indo - Gangetic basin which inherits complex heterogeneous environment, is quite challenging. This study aims at estimating RZSM and understand its variation at the level of Indo - Gangetic basin with changing land use/land cover, topography, crop cycles, soil properties, temperature and precipitation patterns using two satellite derived soil moisture datasets operating at distinct frequencies with different principles of acquisition. Two surface soil moisture datasets are derived from AMSR-2 (6.9 GHz - `C' Band) and SMOS (1.4 GHz - `L' band) passive microwave sensors with coarse spatial resolution. The Soil Water Index (SWI), accounting for soil moisture from the surface, is derived by considering a theoretical two-layered water balance model and contributes in ascertaining soil moisture at the vadose zone. This index is evaluated against the widely used modelled soil moisture dataset of GLDAS - NOAH, version 2.1. This research enhances the domain of utilising the modelled soil moisture dataset, wherever the ground dataset is unavailable. The coupling between the surface soil moisture and RZSM is analysed for two years (2015-16), by defining a parameter T, the characteristic time length. The study demonstrates that deriving an optimal value of T for estimating SWI at a certain location is a function of various factors such as land, meteorological, and agricultural characteristics.

  15. Origin and fate of atmospheric moisture over continents

    NARCIS (Netherlands)

    Van der Ent, R.J.; Savenije, H.H.G.; Schaefli, B.; Steele-Dunne, S.C.

    2010-01-01

    There has been a long debate on the extent to which precipitation relies on terrestrial evaporation (moisture recycling). In the past, most research focused on moisture recycling within a certain region only. This study makes use of new definitions of moisture recycling to study the complete process

  16. A Systematic Method of Assessing the Durability of Wood-Frame Wall Assemblies

    DEFF Research Database (Denmark)

    Lacasse, Michael A.; Morelli, Martin

    2016-01-01

    The long-term performance in respect to moisture management within any wall assembly depends on the hygrothermal response of the wall. Critical factors in estimating the longevity of wood-frame structures include limiting the temperature range, wood moisture content, and time of exposure to condi......The long-term performance in respect to moisture management within any wall assembly depends on the hygrothermal response of the wall. Critical factors in estimating the longevity of wood-frame structures include limiting the temperature range, wood moisture content, and time of exposure...... to the effects of moisture accumulation in wall cavities. Several approaches to assessing the vulnerability of wood-frame structures to deterioration have been developed in recent years, some of which suggest applying a limit-states design approach to the performance assessment of the assembly. In this paper......, a limit-states design approach is described that forms the basis of a performance assessment method for wood-frame wall assemblies. The approach is based on the requirements set out in ISO 13823. The approach, developed for the Moisture Management of Exterior Wall Systems (MEWS) project, is described...

  17. Quantitative identification of moisture sources over the Tibetan Plateau and the relationship between thermal forcing and moisture transport

    Science.gov (United States)

    Pan, Chen; Zhu, Bin; Gao, Jinhui; Kang, Hanqing; Zhu, Tong

    2018-02-01

    Despite the importance of the Tibetan Plateau (TP) to the surrounding water cycle, the moisture sources of the TP remain uncertain. In this study, the moisture sources of the TP are quantitatively identified based on a 33-year simulation with a horizontal resolution of 1.9° × 2.5° using the Community Atmosphere Model version 5.1 (CAM5.1), in which atmospheric water tracer technology is incorporated. Results demonstrate that the major moisture sources differ over the southern TP (STP) and northern TP (NTP). During the winter, Africa, the TP, and India are the dominant source regions, contributing nearly half of the water vapour over the STP. During the summer, the tropical Indian Ocean (TIO) supplies 28.5 ± 3.6% of the water vapour over the STP and becomes the dominant source region. The dominant moisture source regions of the water vapour over the NTP are Africa (19.0 ± 2.8%) during the winter and the TP (25.8 ± 2.4%) during the summer. The overall relative contribution of each source region to the precipitation is similar to the contribution to the water vapour over the TP. Like most models, CAM5.1 generally overestimates the precipitation over the TP, yielding uncertainty in the absolute contributions to the precipitation. Composite analyses exhibit significant variations in the TIO-supplied moisture transport and precipitation over the STP during the summer alongside anomalous TP heating. This relationship between moisture transport from the TIO and the TP heating primarily involves the dynamic change in the TIO-supplied moisture flux, which further controls the variation in the TIO-contributed precipitation over the STP.

  18. Moisture sorption isotherms and thermodynamic properties of bovine leather

    Science.gov (United States)

    Fakhfakh, Rihab; Mihoubi, Daoued; Kechaou, Nabil

    2018-04-01

    This study was aimed at the determination of bovine leather moisture sorption characteristics using a static gravimetric method at 30, 40, 50, 60 and 70 °C. The curves exhibit type II behaviour according to the BET classification. The sorption isotherms fitting by seven equations shows that GAB model is able to reproduce the equilibrium moisture content evolution with water activity for moisture range varying from 0.02 to 0.83 kg/kg d.b (0.9898 thermodynamic properties such as isosteric heat of sorption, sorption entropy, spreading pressure, net integral enthalpy and entropy. Net isosteric heat of sorption and differential entropy were evaluated through direct use of moisture isotherms by applying the Clausius-Clapeyron equation and used to investigate the enthalpy-entropy compensation theory. Both sorption enthalpy and entropy for desorption increase to a maximum with increasing moisture content, and then decrease sharply with rising moisture content. Adsorption enthalpy decreases with increasing moisture content. Whereas, adsorption entropy increases smoothly with increasing moisture content to a maximum of 6.29 J/K.mol. Spreading pressure increases with rising water activity. The net integral enthalpy seemed to decrease and then increase to become asymptotic. The net integral entropy decreased with moisture content increase.

  19. Exploiting Soil Moisture, Precipitation, and Streamflow Observations to Evaluate Soil Moisture/Runoff Coupling in Land Surface Models

    Science.gov (United States)

    Crow, W. T.; Chen, F.; Reichle, R. H.; Xia, Y.; Liu, Q.

    2018-05-01

    Accurate partitioning of precipitation into infiltration and runoff is a fundamental objective of land surface models tasked with characterizing the surface water and energy balance. Temporal variability in this partitioning is due, in part, to changes in prestorm soil moisture, which determine soil infiltration capacity and unsaturated storage. Utilizing the National Aeronautics and Space Administration Soil Moisture Active Passive Level-4 soil moisture product in combination with streamflow and precipitation observations, we demonstrate that land surface models (LSMs) generally underestimate the strength of the positive rank correlation between prestorm soil moisture and event runoff coefficients (i.e., the fraction of rainfall accumulation volume converted into stormflow runoff during a storm event). Underestimation is largest for LSMs employing an infiltration-excess approach for stormflow runoff generation. More accurate coupling strength is found in LSMs that explicitly represent subsurface stormflow or saturation-excess runoff generation processes.

  20. The Effect of Temperature on Moisture Transport in Concrete.

    Science.gov (United States)

    Wang, Yao; Xi, Yunping

    2017-08-09

    Most concrete structures and buildings are under temperature and moisture variations simultaneously. Thus, the moisture transport in concrete is driven by the moisture gradient as well as the temperature gradient. This paper presents an experimental approach for determining the effect of different temperature gradients on moisture distribution profiles in concrete. The effect of elevated temperatures under isothermal conditions on the moisture transport was also evaluated, and found not to be significant. The non-isothermal tests show that the temperature gradient accelerates the moisture transport in concrete. The part of increased moisture transfer due to the temperature gradient can be quantified by a coupling parameter D HT , which can be determined by the present test data. The test results indicated that D HT is not a constant but increases linearly with the temperature variation. A material model was developed for D HT based on the experimental results obtained in this study.

  1. Moisture ingress into electronics enclosures under isothermal conditions

    DEFF Research Database (Denmark)

    Staliulionis, Zygimantas; Jabbaribehnam, Mirmasoud; Hattel, Jesper Henri

    2016-01-01

    loads are still not understood well by design engineers, therefore this field has become one of the bottlenecks in the electronics system design. The objective of this paper is to model moisture ingress into an electronics enclosure under isothermal conditions. The moisture diffusion model is based......The number of electronics used in outdoor environment is constantly growing. The humidity causes about 19 % of all electronics failures and, especially, moisture increases these problems due to the ongoing process of miniaturization and lower power consumption of electronic components. Moisture...

  2. Moisture sorption isotherms of dehydrated whey proteins

    OpenAIRE

    Suzana Rimac Brnčić; Vesna Lelas; Zoran Herceg; Marija Badanjak

    2010-01-01

    Moisture sorption isotherms describe the relation between the moisture content of the dry material (food) and relative humidity of the surrounding environment. The data obtained are important in modelling of drying process conditions, packaging and shelf-life stability of food that will provide maximum retaining of aroma, colour and texture as well as nutritive and biological value. The objective of this research was to establish the equilibrium moisture content and water activity, as well as...

  3. Experiments on moisture form of concrete and adhesion of paints

    International Nuclear Information System (INIS)

    Kita, Daizo; Sumino, Masahiro

    1975-01-01

    It is necessary for radiation-resisting paints to adhere tightly to concrete in order to exhibit superior effects. As adhesion of paints to concrete is greatly affected by moisture content of concrete, this content is checked severely in the field. However, it may be considered that adhesion will be affected by the form of the moisture in the concrete also. Therefore, experiments were conducted with mortar to investigate the interrelations between pF-moisture content, moisture form and adhesion of paint. The following results were obtained: 1) Adhesion of paint becomes stronger as moisture content falls. 2) Adhesion strength of paint rises sharply until moisture content falls to a pF-value of 5.5 after which the strength is increased gradually until moisture content reaches pF of 7.0. 3) The pF-moisture content of 5.5 varies greatly depending on the mix proportions of mortar, but the form of moisture in such cases remains fixed and unchanged. (auth.)

  4. Microwave bale moisture sensing: Field trial

    Science.gov (United States)

    A microwave moisture measurement technique was developed for moisture sensing of cotton bales after the bale press. The technique measures the propagation delay of a microwave signal that is transmitted through the cotton bale. This research conducted a field trial to test the sensor in a commercial...

  5. Moisture Buffer Effect and its Impact on Indoor Environment

    DEFF Research Database (Denmark)

    Zhang, Mingjie; Qin, Menghao; Chen, Zhi

    2017-01-01

    The moisture buffer effect of building materials may have great influence on indoor hygrothermal environment. In order to characterize the moisture buffering ability of materials, the basic concept of moisture buffer value (MBV) is adopted. Firstly, a theoretical correction factor is introduced...... in this paper. The moisture uptake/release by hygroscopic materials can be calculated with the factor and the basic MBV. Furthermore, the validation of the correction factor is carried out. The impact of moisture buffering on indoor environment is assessed by using numerical simulations. The results show...

  6. State of the Art in Large-Scale Soil Moisture Monitoring

    Science.gov (United States)

    Ochsner, Tyson E.; Cosh, Michael Harold; Cuenca, Richard H.; Dorigo, Wouter; Draper, Clara S.; Hagimoto, Yutaka; Kerr, Yan H.; Larson, Kristine M.; Njoku, Eni Gerald; Small, Eric E.; hide

    2013-01-01

    Soil moisture is an essential climate variable influencing land atmosphere interactions, an essential hydrologic variable impacting rainfall runoff processes, an essential ecological variable regulating net ecosystem exchange, and an essential agricultural variable constraining food security. Large-scale soil moisture monitoring has advanced in recent years creating opportunities to transform scientific understanding of soil moisture and related processes. These advances are being driven by researchers from a broad range of disciplines, but this complicates collaboration and communication. For some applications, the science required to utilize large-scale soil moisture data is poorly developed. In this review, we describe the state of the art in large-scale soil moisture monitoring and identify some critical needs for research to optimize the use of increasingly available soil moisture data. We review representative examples of 1) emerging in situ and proximal sensing techniques, 2) dedicated soil moisture remote sensing missions, 3) soil moisture monitoring networks, and 4) applications of large-scale soil moisture measurements. Significant near-term progress seems possible in the use of large-scale soil moisture data for drought monitoring. Assimilation of soil moisture data for meteorological or hydrologic forecasting also shows promise, but significant challenges related to model structures and model errors remain. Little progress has been made yet in the use of large-scale soil moisture observations within the context of ecological or agricultural modeling. Opportunities abound to advance the science and practice of large-scale soil moisture monitoring for the sake of improved Earth system monitoring, modeling, and forecasting.

  7. Moisture Metrics Project

    Energy Technology Data Exchange (ETDEWEB)

    Schuchmann, Mark

    2011-08-31

    the goal of this project was to determine the optimum moisture levels for biomass processing for pellets commercially, by correlating data taken from numerous points in the process, and across several different feedstock materials produced and harvested using a variety of different management practices. This was to be done by correlating energy consumption and material through put rates with the moisture content of incoming biomass ( corn & wheat stubble, native grasses, weeds, & grass straws), and the quality of the final pellet product.This project disseminated the data through a public website, and answering questions form universities across Missouri that are engaged in biomass conversion technologies. Student interns from a local university were employed to help collect data, which enabled them to learn firsthand about biomass processing.

  8. Evaluating ESA CCI Soil Moisture in East Africa

    Science.gov (United States)

    McNally, Amy; Shukla, Shraddhanand; Arsenault, Kristi R.; Wang, Shugong; Peters-Lidard, Christa D.; Verdin, James P.

    2016-01-01

    To assess growing season conditions where ground based observations are limited or unavailable, food security and agricultural drought monitoring analysts rely on publicly available remotely sensed rainfall and vegetation greenness. There are also remotely sensed soil moisture observations from missions like the European Space Agency (ESA) Soil Moisture and Ocean Salinity (SMOS) and NASAs Soil Moisture Active Passive (SMAP), however these time series are still too short to conduct studies that demonstrate the utility of these data for operational applications, or to provide historical context for extreme wet or dry events. To promote the use of remotely sensed soil moisture in agricultural drought and food security monitoring, we use East Africa as a case study to evaluate the quality of a 30+ year time series of merged active-passive microwave soil moisture from the ESA Climate Change Initiative (CCI-SM). Compared to the Normalized Difference Vegetation index (NDVI) and modeled soil moisture products, we found substantial spatial and temporal gaps in the early part of the CCI-SM record, with adequate data coverage beginning in 1992. From this point forward, growing season CCI-SM anomalies were well correlated (R greater than 0.5) with modeled, seasonal soil moisture, and in some regions, NDVI. We use correlation analysis and qualitative comparisons at seasonal time scales to show that remotely sensed soil moisture can add information to a convergence of evidence framework that traditionally relies on rainfall and NDVI in moderately vegetated regions.

  9. development and testing of a capacitive digital soil moisture metre

    African Journals Online (AJOL)

    user

    soil moisture meter using the NE555 timer and micro controller as a major electronic component ... relationship between the moisture content process and the digital soil moisture meter. ..... the moisture contents showing that the infiltration of.

  10. Determining seed moisture in Quercus

    Science.gov (United States)

    F. T. Bonner

    1974-01-01

    The air-oven method with drying times 7 to 8 hours shorter than those now prescribed in the ISTA rules proved adequate for determining moisture contents in acorns of several North American oaks. Schedules of 8 hours at 105°C for Quercus muehlenbergii and 9 hours at 105°C for Q.shumardii and Q.nigra gave moisture contents within three percentage points of those obtained...

  11. 46 CFR 154.1715 - Moisture control.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Moisture control. 154.1715 Section 154.1715 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... § 154.1715 Moisture control. When a vessel is carrying sulfur dioxide, the master shall ensure that: (a...

  12. NOAA Soil Moisture Products System (SMOPS) Daily Blended Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Soil Moisture Operational Products System (SMOPS) combines soil moisture retrievals from multiple satellite sensors to provide a global soil moisture map with...

  13. Interfacial Shear Strength Evaluation of Pinewood Residue/High-Density Polyethylene Composites Exposed to UV Radiation and Moisture Absorption-Desorption Cycles

    Directory of Open Access Journals (Sweden)

    Soledad C. Pech-Cohuo

    2016-03-01

    Full Text Available In outdoor applications, the mechanical performance of wood-plastic composites (WPCs is affected by UV radiation, facilitating moisture intake and damaging the wood-polymer interfacial region. The purpose of this study was to evaluate the effect of moisture absorption-desorption cycles (MADCs, and the exposure to UV radiation on the interfacial shear strength (IFSS of WPCs with 40% pinewood residue and 60% high-density polyethylene. One of the WPCs incorporated 5% coupling agent (CA with respect to wood content. The IFSS was evaluated following the Iosipescu test method. The specimens were exposed to UV radiation using an accelerated weathering test device and subsequently subjected to four MADCs. Characterization was also performed by scanning electron microscopy (SEM and Fourier transform infrared spectroscopy (FTIR. The absorption and desorption of moisture was slower in non-UV-irradiated WPCs, particularly in those with the CA. The UV radiation did not significantly contribute to the loss of the IFSS. Statistically, the CA had a favorable effect on the IFSS. Exposure of the samples to MADCs contributed to reduce the IFSS. The FTIR showed lignin degradation and the occurrence of hydrolysis reactions after exposure to MADCs. SEM confirmed that UV radiation did not significantly affect the IFSS.

  14. The study of high precision neutron moisture gauge

    International Nuclear Information System (INIS)

    Liu Shengkang; Bao Guanxiong; Sang Hai; Zhu Yuzhen

    1993-01-01

    The principle, structure and calibration experiment of the high precision neutron moisture gauge (insertion type) are described. The gauge has been appraised. The precision of the measuring moisture of coke is lower than 0.5%, and the range of the measuring moisture is 2%-12%. The economic benefit of the gauge application is good

  15. CFD modelling of moisture interactions between air and constructions

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Woloszyn, Monika; Hohota, Raluca

    2005-01-01

    There is a strong demand for accurate moisture modelling since moisture poses a risk for both the constructions and the indoor climate. Thus, in this investigation there is special focus on moisture modelling. The paper describes a new model based on a CFD tool that is enhanced to include both...... detailed modelling of airflows in rooms and heat and moisture transfer in walls by applying them as fluid walls. In a 3D configuration the impact of different boundary conditions are investigated and the results are discussed. The changes of boundary conditions that are studied are velocity, moisture...

  16. High moisture airtight storage of barley and triticale: Effect of moisture level and grain processing on nitrogen and phosphorus solubility

    DEFF Research Database (Denmark)

    Ton Nu, Mai Anh; Blaabjerg, Karoline; Labouriau, Rodrigo

    2015-01-01

    The aim of this study was to evaluate the effect of storage time, grain processing (whole vs. rolled) and the combination of phytase, xylanase, β-glucanase and protease on nitrogen (N) and phosphorus (P) solubility during high moisture airtight (HMA) storage of barley and triticale at various...... moisture levels (20, 23, 26 and 29% moisture) and to compare HMA storage of cereals with dry storage for 49 days. Dry stored barley and triticale (10 and 13% moisture, respectively) were kept in 10 L plastic buckets for 0 and 49 days. HMA stored cereals were kept in airtight bags (400 g per bag) at 15 °C......) in HMA storage at 29% moisture to a greater extent compared with dry storage (P levels increased P solubility (rolled barley, whole and rolled triticale) and N solubility (whole and rolled triticale) linearly and decreased Phytate P:Total P (rolled barley) linearly...

  17. Avaliação do teor de umidade da madeira de Eucalyptus grandis por medidores elétricos resistivos. Evaluation of the Eucalyptus grandis lumber moisture content by resistancetype moisture meters.

    Directory of Open Access Journals (Sweden)

    João Eduardo Guarnetti dos SANTOS

    2006-01-01

    Full Text Available O presente estudo teve como objetivoverificar a precisão de dois tipos de medidoreselétricos de teor de umidade durante o processo desecagem da madeira de Eucalyptus grandis. Foramretiradas amostras representativas de 14 tábuas deEucalyptus grandis e secas em estufa elétrica a40 ºC de temperatura, até que o material atingisse10% de umidade. Durante a secagem foramdeterminados, periodicamente, o teor de umidadeatravés do método de massas correntes e deverificações simultâneas com um medidor elétricoportátil (EMM e com o sistema de controle de umsecador convencional (KCS. Os resultados mostraramque: (1 o sensor de umidade KCS pode substituiro método gravimétrico durante a secagem damadeira; (2 o medidor do teor de umidade EMMsubestima os reais teores de umidade durante asecagem da madeira e não é indicado parasubstituir o método gravimétrico de determinação de umidade.The aim of the study was to evaluate theprecision of two types of electric moisture metersduring the drying process of Eucalyptus grandisboards. Samples were obtained from 14 boards ofEucalyptus grandis and they were dried in electriclaboratory oven at 40 ºC of temperature, until thewood achieve 10% of moisture content. During thedrying, the moisture content was determined bygravimetric method and simultaneous checks by anelectric moisture meter (EMM and by kilncontrol system (KCS. The results showed that:(1 the KCS can replace the gravimetric methodduring the wood drying; (2 the EMMunderestimate the real moisture content during thedrying of boards and it is not indicate as substituteof the gravimetric method.

  18. Dampness and Moisture Problems in Norwegian Homes

    Directory of Open Access Journals (Sweden)

    Rune Becher

    2017-10-01

    Full Text Available The occurrence of dampness and mold in the indoor environment is associated with respiratory-related disease outcomes. Thus, it is pertinent to know the magnitude of such indoor environment problems to be able to estimate the potential health impact in the population. In the present study, the moisture damage in 10,112 Norwegian dwellings was recorded based on building inspection reports. The levels of moisture damage were graded based on a condition class (CC, where CC0 is immaculate and CC1 acceptable (actions not required, while CC2 and CC3 indicate increased levels of damage that requires action. Of the 10,112 dwellings investigated, 3125 had verified moisture or mold damage. This amounts to 31% of the surveyed dwellings. Of these, 27% had CC2 as the worst grade, whereas 4% had CC3 as the worst grade level. The room types and building structures most prone to moisture damage were (in rank order crawl spaces, basements, un-insulated attics, cooling rooms, and bathrooms. The high proportion of homes with moisture damage indicate a possible risk for respiratory diseases in a relatively large number of individuals, even if only the more extensive moisture damages and those located in rooms where occupants spend the majority of their time would have a significant influence on adverse health effects.

  19. Correlation between laser-induced breakdown spectroscopy signal and moisture content

    International Nuclear Information System (INIS)

    Liu, Yuan; Gigant, Lionel; Baudelet, Matthieu; Richardson, Martin

    2012-01-01

    The possibility of using Laser-Induced Breakdown Spectroscopy (LIBS) for measuring the moisture content of fresh food samples is studied. The normalized line emission of oxygen is highly correlated with the moisture content of the sample, cheese in our case, and can be used as a moisture marker in situations where oxygen interference from the matrix is not a critical issue. The linear correlation between the oxygen signal and the moisture content in the sample shows great potential for using LIBS as an alternative spectroscopic method for moisture monitoring. - Highlights: ► Quantitative moisture measurement by LIBS. ► Use of matrix effects and normalization for physical information on the sample. ► Use of signal from oxygen and CN radical in air background for moisture measurement.

  20. Soil moisture in sessile oak forest gaps

    Science.gov (United States)

    Zagyvainé Kiss, Katalin Anita; Vastag, Viktor; Gribovszki, Zoltán; Kalicz, Péter

    2015-04-01

    By social demands are being promoted the aspects of the natural forest management. In forestry the concept of continuous forest has been an accepted principle also in Hungary since the last decades. The first step from even-aged stand to continuous forest can be the forest regeneration based on gap cutting, so small openings are formed in a forest due to forestry interventions. This new stand structure modifies the hydrological conditions for the regrowth. Without canopy and due to the decreasing amounts of forest litter the interception is less significant so higher amount of precipitation reaching the soil. This research focuses on soil moisture patterns caused by gaps. The spatio-temporal variability of soil water content is measured in gaps and in surrounding sessile oak (Quercus petraea) forest stand. Soil moisture was determined with manual soil moisture meter which use Time-Domain Reflectometry (TDR) technology. The three different sizes gaps (G1: 10m, G2: 20m, G3: 30m) was opened next to Sopron on the Dalos Hill in Hungary. First, it was determined that there is difference in soil moisture between forest stand and gaps. Second, it was defined that how the gap size influences the soil moisture content. To explore the short term variability of soil moisture, two 24-hour (in growing season) and a 48-hour (in dormant season) field campaign were also performed in case of the medium-sized G2 gap along two/four transects. Subdaily changes of soil moisture were performed. The measured soil moisture pattern was compared with the radiation pattern. It was found that the non-illuminated areas were wetter and in the dormant season the subdaily changes cease. According to our measurements, in the gap there is more available water than under the forest stand due to the less evaporation and interception loss. Acknowledgements: The research was supported by TÁMOP-4.2.2.A-11/1/KONV-2012-0004 and AGRARKLIMA.2 VKSZ_12-1-2013-0034.

  1. Irrigation scheduling using soil moisture sensors

    Science.gov (United States)

    Soil moisture sensors were evaluated and used for irrigation scheduling in humid region. Soil moisture sensors were installed in soil at depths of 15cm, 30cm, and 61cm belowground. Soil volumetric water content was automatically measured by the sensors in a time interval of an hour during the crop g...

  2. Moisture separator reheaters for nuclear power plants

    International Nuclear Information System (INIS)

    Miyoshi, Michizo; Yonemura, Katsutoshi

    1974-01-01

    In the light water reactor plants using BWRS or PWRS, the pressure and temperature of steam at the inlet of turbines are low, and the steam is moist, as compared with the case of thermal power plants. Therefore, moisture separator/reheaters are used between high and low pressure turbines. The steam from a high pressure turbine enters a manifold, and goes zigzag through vertical plate separator elements, its moisture is removed from the steam. Then, after being reheated with the steam bled from the high pressure turbine and directly from a reactor, the steam is fed into a low pressure turbine. The development and test made on the components of a moisture separaotr/reheater and the overall model experiment are described together with the mechanism of moisture separation and reheating. (Mori, K.)

  3. The global distribution and dynamics of surface soil moisture

    Science.gov (United States)

    McColl, Kaighin A.; Alemohammad, Seyed Hamed; Akbar, Ruzbeh; Konings, Alexandra G.; Yueh, Simon; Entekhabi, Dara

    2017-01-01

    Surface soil moisture has a direct impact on food security, human health and ecosystem function. It also plays a key role in the climate system, and the development and persistence of extreme weather events such as droughts, floods and heatwaves. However, sparse and uneven observations have made it difficult to quantify the global distribution and dynamics of surface soil moisture. Here we introduce a metric of soil moisture memory and use a full year of global observations from NASA's Soil Moisture Active Passive mission to show that surface soil moisture--a storage believed to make up less than 0.001% of the global freshwater budget by volume, and equivalent to an, on average, 8-mm thin layer of water covering all land surfaces--plays a significant role in the water cycle. Specifically, we find that surface soil moisture retains a median 14% of precipitation falling on land after three days. Furthermore, the retained fraction of the surface soil moisture storage after three days is highest over arid regions, and in regions where drainage to groundwater storage is lowest. We conclude that lower groundwater storage in these regions is due not only to lower precipitation, but also to the complex partitioning of the water cycle by the surface soil moisture storage layer at the land surface.

  4. Moisture content analysis of covered uranium mill tailings

    International Nuclear Information System (INIS)

    Mayer, D.W.; Beedlow, P.A.; Cadwell, L.L.

    1981-12-01

    The use of vegetation and rock covers to stabilize uranium mill tailings cover systems is being investigated by Pacific Northwest Laboratory. A modeling study of moisture movement through the tailings and cover layers was initiated to determine the effect of the stabilizing techniques. The cover system was simulated under climatic conditions occurring at Grand Junction, Colorado. The cover consisted of a layer of wet clay/gravel mix followed by a capillary barrier of washed rock and a surface layer of fill soil. Vegetation and rock were used to stabilize the surface layer. The simulation yielded moisture content and moisture storage values for the tailings and cover system along with information about moisture losses due to evaporation, transpiration, and drainage. The study demonstrates that different surface stabilization treatments lead to different degrees of moisture retention in the covered tailings pile. The evapotranspiration from vegetation can result in a relatively stable moisture content. Rock covers, however, may cause drainage to occur because they reduce evaporation and lead to a subsequent increase in moisture content. It is important to consider these effects when designing a surface stabilization treatment. Drainage may contribute to a groundwater pollution problem. A surface treatment that allows the cover system to dry out can increase the risk of atmospheric contamination through elevated radon emission rates

  5. Moisture distribution in sludges based on different testing methods

    Institute of Scientific and Technical Information of China (English)

    Wenyi Deng; Xiaodong Li; Jianhua Yan; Fei Wang; Yong Chi; Kefa Cen

    2011-01-01

    Moisture distributions in municipal sewage sludge, printing and dyeing sludge and paper mill sludge were experimentally studied based on four different methods, i.e., drying test, thermogravimetric-differential thermal analysis (TG-DTA) test, thermogravimetricdifferential scanning calorimetry (TG-DSC) test and water activity test. The results indicated that the moistures in the mechanically dewatered sludges were interstitial water, surface water and bound water. The interstitial water accounted for more than 50% wet basis (wb) of the total moisture content. The bond strength of sludge moisture increased with decreasing moisture content, especially when the moisture content was lower than 50% wb. Furthermore, the comparison among the four different testing methods was presented.The drying test was advantaged by its ability to quantify free water, interstitial water, surface water and bound water; while TG-DSC test, TG-DTA test and water activity test were capable of determining the bond strength of moisture in sludge. It was found that the results from TG-DSC and TG-DTA test are more persuasive than water activity test.

  6. Moisture dependence of positron annihilation rates in molecular substances

    International Nuclear Information System (INIS)

    Singh, J.J.; Holt, W.H.

    1982-01-01

    Positron annihilation rates have been studied in polymers and graphite-polymer composites as a function of their moisture content. The annihilation rates have been found to increase linearly with increasing moisture content in epoxies and polyamides, whereas no definite trends have been observed in polyimides. These experimental results have been used as the basis for the calculation of moisture content of several polymeric test specimens. For example, the directly measured moisture content of a Kevlar specimen was 45.5 + or - 5.0% of saturation value, whereas the moisture content on the basis of the decrease in positron lifetime was calculated to be 46.5 + or - 3.5%. Similarly, the directly measured moisture content of a graphite-epoxy composite (55 v/o fiber) was 19.2 + or - 0.6% of saturation value as opposed to a calculated value of 16.0 + or - 5.0%

  7. Response of bacteria in wastewater sludge to moisture loss by evaporation and effect of moisture content on bacterial inactivation by ionizing radiation

    International Nuclear Information System (INIS)

    Ward, R.L.; Yeager, J.G.; Ashley, C.S.

    1981-01-01

    Two studies were carried out to determine the influence of moisture content on the survival of bacteria in raw wastewater sludge. The first study involved the effect of water loss by evaporation on the bacterial population. The second used these dewatered samples to measure the effects of moisture content on the inactivation of bacteria in sludge by ionizing radiation. Both studies involved survival measurements of six representative fecally associated bacteria grown separately in sterilized sludge as well as survival data on bacteria indigenous to sludge. Growth of bacteria was stimulated in sludge during the initial phase of moisture removal by evaporation, but the reduction of moisture content below about 50% by weight caused a proportional decrease in bacterial numbers. The rates of inactivation of bacteria by ionizing radiation in sludge were usually modified to some degree by variations in moisture content. Most bacteria were found to be somewhat protected from ionizing radiation at reduced moisture levels

  8. Moisture parameters and fungal communities associated with gypsum drywall in buildings.

    Science.gov (United States)

    Dedesko, Sandra; Siegel, Jeffrey A

    2015-12-08

    Uncontrolled excess moisture in buildings is a common problem that can lead to changes in fungal communities. In buildings, moisture parameters can be classified by location and include assessments of moisture in the air, at a surface, or within a material. These parameters are not equivalent in dynamic indoor environments, which makes moisture-induced fungal growth in buildings a complex occurrence. In order to determine the circumstances that lead to such growth, it is essential to have a thorough understanding of in situ moisture measurement, the influence of building factors on moisture parameters, and the levels of these moisture parameters that lead to indoor fungal growth. Currently, there are disagreements in the literature on this topic. A literature review was conducted specifically on moisture-induced fungal growth on gypsum drywall. This review revealed that there is no consistent measurement approach used to characterize moisture in laboratory and field studies, with relative humidity measurements being most common. Additionally, many studies identify a critical moisture value, below which fungal growth will not occur. The values defined by relative humidity encompassed the largest range, while those defined by moisture content exhibited the highest variation. Critical values defined by equilibrium relative humidity were most consistent, and this is likely due to equilibrium relative humidity being the most relevant moisture parameter to microbial growth, since it is a reasonable measure of moisture available at surfaces, where fungi often proliferate. Several sources concur that surface moisture, particularly liquid water, is the prominent factor influencing microbial changes and that moisture in the air and within a material are of lesser importance. However, even if surface moisture is assessed, a single critical moisture level to prevent fungal growth cannot be defined, due to a number of factors, including variations in fungal genera and

  9. Correlation between laser-induced breakdown spectroscopy signal and moisture content

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yuan [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States); Gigant, Lionel [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States); Universite Bordeaux 1, 351 cours de la Liberation 33405 Talence Cedex (France); Baudelet, Matthieu, E-mail: baudelet@creol.ucf.edu [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States); Richardson, Martin [Townes Laser Institute, CREOL - The College of Optics and Photonics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States)

    2012-07-15

    The possibility of using Laser-Induced Breakdown Spectroscopy (LIBS) for measuring the moisture content of fresh food samples is studied. The normalized line emission of oxygen is highly correlated with the moisture content of the sample, cheese in our case, and can be used as a moisture marker in situations where oxygen interference from the matrix is not a critical issue. The linear correlation between the oxygen signal and the moisture content in the sample shows great potential for using LIBS as an alternative spectroscopic method for moisture monitoring. - Highlights: Black-Right-Pointing-Pointer Quantitative moisture measurement by LIBS. Black-Right-Pointing-Pointer Use of matrix effects and normalization for physical information on the sample. Black-Right-Pointing-Pointer Use of signal from oxygen and CN radical in air background for moisture measurement.

  10. CPC Soil Moisture

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The monthly data set consists of a file containing 1/2 degree monthly averaged soil moisture water height equivalents for the globe from 1948 onwards. Values are...

  11. [Bare Soil Moisture Inversion Model Based on Visible-Shortwave Infrared Reflectance].

    Science.gov (United States)

    Zheng, Xiao-po; Sun, Yue-jun; Qin, Qi-ming; Ren, Hua-zhong; Gao, Zhong-ling; Wu, Ling; Meng, Qing-ye; Wang, Jin-liang; Wang, Jian-hua

    2015-08-01

    Soil is the loose solum of land surface that can support plants. It consists of minerals, organics, atmosphere, moisture, microbes, et al. Among its complex compositions, soil moisture varies greatly. Therefore, the fast and accurate inversion of soil moisture by using remote sensing is very crucial. In order to reduce the influence of soil type on the retrieval of soil moisture, this paper proposed a normalized spectral slope and absorption index named NSSAI to estimate soil moisture. The modeling of the new index contains several key steps: Firstly, soil samples with different moisture level were artificially prepared, and soil reflectance spectra was consequently measured using spectroradiometer produced by ASD Company. Secondly, the moisture absorption spectral feature located at shortwave wavelengths and the spectral slope of visible wavelengths were calculated after analyzing the regular spectral feature change patterns of different soil at different moisture conditions. Then advantages of the two features at reducing soil types' effects was synthesized to build the NSSAI. Thirdly, a linear relationship between NSSAI and soil moisture was established. The result showed that NSSAI worked better (correlation coefficient is 0.93) than most of other traditional methods in soil moisture extraction. It can weaken the influences caused by soil types at different moisture levels and improve the bare soil moisture inversion accuracy.

  12. Use a microwave oven to determine the moisture content of sunflower

    International Nuclear Information System (INIS)

    Backer, L.F.; Walz, A.W.

    1987-01-01

    Much of the sunflower crop in the major producing areas of the United States requires artificial drying because of late crop maturity. Plant growth regulators permit earlier harvest by accelerating the maturation rate of the plant; research indicates that use of the growth regulator would result in approximately 10-14 days earlier maturation. Effectiveness of the chemical is dependent on timely application at relatively high moisture contents (50 to 55 percent). A rapid means of determining seed moisture content is required so the chemical can be applied at the proper growth stage . Additionally, sunflower is often harvested at moisture contents of more than 17 percent. Most electronic moisture meters are not calibrated for moisture contents this high and the accuracy of most moisture meters decreases with increasing moisture content. A recent study has shown that a conventional microwave oven can successfully be used to very rapidly determine the moisture content of high moisture sunflower seeds to indicate proper growth stage for the application of plant growth regulators. The microwave oven could also be used with reasonable accuracy to check harvest moisture content down to about 15 percent. At lower moisture contents, it would be advisable to use a calibrated electronic moisture meter

  13. Microwave moisture sensing of wet bales

    Science.gov (United States)

    Sensing of moisture in very wet lint bales is unique due to the fact that moisture distribution is typically non-uniform and can in some instances be highly localized. This issue is even further complicated by the use of a sensor that reads only a portion of the bale and/or with a sensor that provid...

  14. Logging effects on soil moisture losses

    Science.gov (United States)

    Robert R. Ziemer

    1978-01-01

    Abstract - The depletion of soil moisture within the surface 15 feet by an isolated mature sugar pine and an adjacent uncut forest in the California Sierra Nevada was measured by the neutron method every 2 weeks for 5 consecutive summers. Soil moisture recharge was measured periodically during the intervening winters. Groundwater fluctuations within the surface 50...

  15. Moisture ingress into electronics enclosures under isothermal conditions

    International Nuclear Information System (INIS)

    Staliulionis, Ž.; Jabbari, M.; Hattel, J. H.

    2016-01-01

    The number of electronics used in outdoor environment is constantly growing. The humidity causes about 19 % of all electronics failures and, especially, moisture increases these problems due to the ongoing process of miniaturization and lower power consumption of electronic components. Moisture loads are still not understood well by design engineers, therefore this field has become one of the bottlenecks in the electronics system design. The objective of this paper is to model moisture ingress into an electronics enclosure under isothermal conditions. The moisture diffusion model is based on a 1D quasi-steady state (QSS) approximation for Fick’s second law. This QSS approach is also described with an electrical analogy which gives a fast tool in modelling of the moisture response. The same QSS method is applied to ambient water vapour variations. The obtained results are compared to an analytical solution and very good agreement is found.

  16. A biomimic thermal fabric with high moisture permeability

    Directory of Open Access Journals (Sweden)

    Fan Jie

    2013-01-01

    Full Text Available Moisture comfort is an essential factor for functional property of thermal cloth, especially for thick thermal cloth, since thick cloth may hinder effective moisture permeation, and high moisture concentration in the micro-climate between skin and fabric would cause cold feeling. Here, we report a biomimic thermal fabric with excellent warm retention and moisture management properties. In this fabric, the warp yarn system constructs many tree-shaped channel nets in the thickness direction of the fabric. Experimental result indicates that the special hierarchic configuration of warp yarns endows the biomimic thermal fabric with a better warm retention and water vapor management properties compared with the traditional fabrics.

  17. Non-isothermal Moisture Transport Through Insulation Materials

    DEFF Research Database (Denmark)

    Peuhkuri, Ruut Hannele; Rode, Carsten; Hansen, Kurt Kielsgaard

    2008-01-01

    An experimental investigation was conducted in order to draw some conclusions on the magnitude of moisture transport due to temperature gradient on a range of porous light-weight building materials. A special constructed non-isothermal set-up allowed the creation of a temperature gradient of 10K...... and given humidity gradient over the sample. The resulting moisture ux as well as the hygrothermal states around and within the material were monitored. The hypothesis of relative humidity being a driving force for non-isothermal moisture transport already in the hygroscopic range could not be confirmed....... On the contrary, indications exist that the temperature gradient itself is driving the moisture from the warm side towards the cold side. An attempt to identify and quantify the single contributions of the different transport forms involved is also presented. The diferent results gave, however, diverging...

  18. Moisture dependence of positron annihilation rates in molecular substances

    International Nuclear Information System (INIS)

    Singh, J.J.; Holt, W.H.; Mock, W. Jr.

    1982-01-01

    Positron annihilation rates have been studied in polymers and graphite-polymer composites as a function of their moisture content. The annihilation rates have been found to increase linearly with increasing moisture content in epoxies and polyamides, whereas no definite trends have been observed in the polymides. These experimental results have been used as the basis for the calculation of moisture content of several polymeric test specimens. For example, the directly measured moisture content of a Kevlar/epoxy specimen (55 v/o fiber) was 45.5 +- 5.0% of saturation value, whereas the moisture content on the basis of the decrease in positron lifetime was calculated to be 46.5 +- 3.5%. Similarly, the directly measured moisture content of a graphite/epoxy composite (55 v/o fiber) was 19.2 +- 0.6% of saturation value as opposed to a calculated value of 16.0 +- 5.0%. (orig.)

  19. Surface Moisture Measurement System Operation and Maintenance Manual

    International Nuclear Information System (INIS)

    Ritter, G.A.; Pearce, K.L.; Stokes, T.L.

    1995-12-01

    This operations and maintenance manual addresses deployment, equipment and field hazards, operating instructions, calibration verification, removal, maintenance, and other pertinent information necessary to safely operate and store the Surface Moisture Measurement System (SMMS) and Liquid Observation Well Moisture Measurement System (LOWMMS). These systems were developed primarily in support of Tank Waste Remediation System (TWRS) Safety Programs for moisture measurement in organic and ferrocyanide watch list tanks

  20. Cone penetrometer moisture probe acceptance test report

    International Nuclear Information System (INIS)

    Barnes, G.A.

    1996-01-01

    This Acceptance Test Report (ATR) documents the results of WHC-SD-WM-ATP-146 (Prototype Cone Penetrometer Moisture Probe Acceptance Test Procedure) and WHC-SD-WM-ATP-145 (Cone Penetrometer Moisture Probe Acceptance Test Procedure). The master copy of WHC-SD-WM-ATP-145 can be found in Appendix A and the master copy of WHC-SD-WM-ATP-146 can be found in Appendix B. Also included with this report is a matrix showing design criteria of the cone penetrometer moisture probe and the verification method used (Appendix C)

  1. Propagation of soil moisture memory to runoff and evapotranspiration

    Science.gov (United States)

    Orth, R.; Seneviratne, S. I.

    2012-10-01

    As a key variable of the land-climate system soil moisture is a main driver of runoff and evapotranspiration under certain conditions. Soil moisture furthermore exhibits outstanding memory (persistence) characteristics. Also for runoff many studies report distinct low frequency variations that represent a memory. Using data from over 100 near-natural catchments located across Europe we investigate in this study the connection between soil moisture memory and the respective memory of runoff and evapotranspiration on different time scales. For this purpose we use a simple water balance model in which dependencies of runoff (normalized by precipitation) and evapotranspiration (normalized by radiation) on soil moisture are fitted using runoff observations. The model therefore allows to compute memory of soil moisture, runoff and evapotranspiration on catchment scale. We find considerable memory in soil moisture and runoff in many parts of the continent, and evapotranspiration also displays some memory on a monthly time scale in some catchments. We show that the memory of runoff and evapotranspiration jointly depend on soil moisture memory and on the strength of the coupling of runoff and evapotranspiration to soil moisture. Furthermore we find that the coupling strengths of runoff and evapotranspiration to soil moisture depend on the shape of the fitted dependencies and on the variance of the meteorological forcing. To better interpret the magnitude of the respective memories across Europe we finally provide a new perspective on hydrological memory by relating it to the mean duration required to recover from anomalies exceeding a certain threshold.

  2. Microwave radiometric measurements of soil moisture in Italy

    Directory of Open Access Journals (Sweden)

    G. Macelloni

    2003-01-01

    Full Text Available Within the framework of the MAP and RAPHAEL projects, airborne experimental campaigns were carried out by the IFAC group in 1999 and 2000, using a multifrequency microwave radiometer at L, C and X bands (1.4, 6.8 and 10 GHz. The aim of the experiments was to collect soil moisture and vegetation biomass information on agricultural areas to give reliable inputs to the hydrological models. It is well known that microwave emission from soil, mainly at L-band (1.4 GHz, is very well correlated to its moisture content. Two experimental areas in Italy were selected for this project: one was the Toce Valley, Domodossola, in 1999, and the other, the agricultural area of Cerbaia, close to Florence, where flights were performed in 2000. Measurements were carried out on bare soils, corn and wheat fields in different growth stages and on meadows. Ground data of soil moisture (SMC were collected by other research teams involved in the experiments. From the analysis of the data sets, it has been confirmed that L-band is well related to the SMC of a rather deep soil layer, whereas C-band is sensitive to the surface SMC and is more affected by the presence of surface roughness and vegetation, especially at high incidence angles. An algorithm for the retrieval of soil moisture, based on the sensitivity to moisture of the brightness temperature at C-band, has been tested using the collected data set. The results of the algorithm, which is able to correct for the effect of vegetation by means of the polarisation index at X-band, have been compared with soil moisture data measured on the ground. Finally, the sensitivity of emission at different frequencies to the soil moisture profile was investigated. Experimental data sets were interpreted by using the Integral Equation Model (IEM and the outputs of the model were used to train an artificial neural network to reproduce the soil moisture content at different depths. Keywords: microwave radiometry, soil moisture

  3. Automated Quality Control of in Situ Soil Moisture from the North American Soil Moisture Database Using NLDAS-2 Products

    Science.gov (United States)

    Ek, M. B.; Xia, Y.; Ford, T.; Wu, Y.; Quiring, S. M.

    2015-12-01

    The North American Soil Moisture Database (NASMD) was initiated in 2011 to provide support for developing climate forecasting tools, calibrating land surface models and validating satellite-derived soil moisture algorithms. The NASMD has collected data from over 30 soil moisture observation networks providing millions of in situ soil moisture observations in all 50 states as well as Canada and Mexico. It is recognized that the quality of measured soil moisture in NASMD is highly variable due to the diversity of climatological conditions, land cover, soil texture, and topographies of the stations and differences in measurement devices (e.g., sensors) and installation. It is also recognized that error, inaccuracy and imprecision in the data set can have significant impacts on practical operations and scientific studies. Therefore, developing an appropriate quality control procedure is essential to ensure the data is of the best quality. In this study, an automated quality control approach is developed using the North American Land Data Assimilation System phase 2 (NLDAS-2) Noah soil porosity, soil temperature, and fraction of liquid and total soil moisture to flag erroneous and/or spurious measurements. Overall results show that this approach is able to flag unreasonable values when the soil is partially frozen. A validation example using NLDAS-2 multiple model soil moisture products at the 20 cm soil layer showed that the quality control procedure had a significant positive impact in Alabama, North Carolina, and West Texas. It had a greater impact in colder regions, particularly during spring and autumn. Over 433 NASMD stations have been quality controlled using the methodology proposed in this study, and the algorithm will be implemented to control data quality from the other ~1,200 NASMD stations in the near future.

  4. Moisture damage and asthma: a birth cohort study.

    Science.gov (United States)

    Karvonen, Anne M; Hyvärinen, Anne; Korppi, Matti; Haverinen-Shaughnessy, Ulla; Renz, Harald; Pfefferle, Petra I; Remes, Sami; Genuneit, Jon; Pekkanen, Juha

    2015-03-01

    Excess moisture and visible mold are associated with increased risk of asthma. Only a few studies have performed detailed home visits to characterize the extent and location of moisture damage and mold growth. Structured home inspections were performed in a birth cohort study when the children were 5 months old (on average). Children (N = 398) were followed up to the age of 6 years. Specific immunoglobulin E concentrations were determined at 6 years. Moisture damage and mold at an early age in the child's main living areas (but not in bathrooms or other interior spaces) were associated with the risk of developing physician-diagnosed asthma ever, persistent asthma, and respiratory symptoms during the first 6 years. Associations with asthma ever were strongest for moisture damage with visible mold in the child's bedroom (adjusted odds ratio: 4.82 [95% confidence interval: 1.29-18.02]) and in the living room (adjusted odds ratio: 7.51 [95% confidence interval: 1.49-37.83]). Associations with asthma ever were stronger in the earlier part of the follow-up and among atopic children. No consistent associations were found between moisture damage with or without visible mold and atopic sensitization. Moisture damage and mold in early infancy in the child's main living areas were associated with asthma development. Atopic children may be more susceptible to the effects of moisture damage and mold. Copyright © 2015 by the American Academy of Pediatrics.

  5. Analysis of Moisture Evaporation from Underwear Designed for Fire-Fighters

    Directory of Open Access Journals (Sweden)

    Elena Onofrei

    2015-03-01

    Full Text Available In this study we analysed the effect of moisture on the thermal protective performance of fire-fighter clothing in case of routine fire-fighting conditions. In the first stage of this research we investigated simultaneous heat and moisture transfer through a single-layer fabric, used as underwear for fire-fighters, at different moisture conditions. In the second stage of the study, the underwear in dry and wet state was tested together with protective clothing systems for fire-fighter consisting of three or four layers. It was found that during the evaporation of the moisture, a temperature plateau appeared during which temperatures hardly rose. The energy consumption used for the phase change of moisture located in the assembly dominated the heat transfer process as long as there was moisture present. As soon as all water had evaporated, the temperatures approached the temperatures measured for dry samples. The moisture within the clothing assembly did not lead to increased temperatures compared with the measurements with dry samples. This research has confirmed that moisture can positively affect the thermal protection of a clothing system.

  6. Collective impacts of soil moisture and orography on deep convective thunderstorms

    Science.gov (United States)

    Imamovic, Adel; Schlemmer, Linda; Schär, Christoph

    2017-04-01

    Thunderstorm activity in many land regions peaks in summer, when surface heat fluxes and the atmospheric moisture content reach an annual maximum. Studies using satellite and ground-based observations have shown that the timing and vigor of summer thunderstorms are influenced by the presence of triggering mechanisms such as soil-moisture heterogeneity or orography. In the current process-based study we aim to dissect the combined impact of soil-moisture and orography on moist convection by using convection-resolving climate simulations with idealized landsurface and orographic conditions. First we systematically investigate the sensitivity of moist convection in absence of orography to a mesoscale soil-moisture anomaly, i.e. a region with drier or moister soil. Consistent with previous studies, a high sensitivity of total rain to soil-moisture anomalies over flat terrain is found. The total rain in the presence of a dry soil-moisture anomaly increases linearly if the soil-moisture anomaly is dried: an anomaly that is 50 % dryer than the reference case with a homogeneous soil-moisture distribution produces up to 40 % more rain. The amplitude of this negative response to the dry soil-moisture anomaly cannot be reproduced by either drying or moistening the soil in the whole domain, even when using unrealistic soil-moisture values. A moist soil anomaly showed little impact on total rain. The triggering effects of the soil-moisture anomalies can be reproduced by an isolated mountain of 250 m height. In order to test to what extent the impact of the soil-moisture anomaly and the mountain are additive, the soil-moisture perturbation method is applied to soil-moisture over the isolated mountain. A 250 m high mountain with drier (moister) soil than its surrounding is found to enhance (suppress) rain amounts. However, the sensitivity of rain amount to the soil-moisture anomaly decreases with the mountain height: A 500 m high mountain is already sufficient to eliminate the

  7. Global characterization of surface soil moisture drydowns

    Science.gov (United States)

    McColl, Kaighin A.; Wang, Wei; Peng, Bin; Akbar, Ruzbeh; Short Gianotti, Daniel J.; Lu, Hui; Pan, Ming; Entekhabi, Dara

    2017-04-01

    Loss terms in the land water budget (including drainage, runoff, and evapotranspiration) are encoded in the shape of soil moisture "drydowns": the soil moisture time series directly following a precipitation event, during which the infiltration input is zero. The rate at which drydowns occur—here characterized by the exponential decay time scale τ—is directly related to the shape of the loss function and is a key characteristic of global weather and climate models. In this study, we use 1 year of surface soil moisture observations from NASA's Soil Moisture Active Passive mission to characterize τ globally. Consistent with physical reasoning, the observations show that τ is lower in regions with sandier soils, and in regions that are more arid. To our knowledge, these are the first global estimates of τ—based on observations alone—at scales relevant to weather and climate models.

  8. Molecular Sensors for Moisture Detection by Moessbauer Spectroscopy

    International Nuclear Information System (INIS)

    Renz, F.; Souza, P. A. de; Klingelhoefer, G.; Goodwin, H. A.

    2002-01-01

    A parameter of importance in various industrial and commercial applications is sensitivity to moisture. A new class of molecular sensors which enable the qualitative and quantitative determination of air moisture (high selectivity and sensitivity) by application of Moessbauer spectroscopy as the probe technique has been investigated. The electronic properties of the iron-containing sensor depend upon the presence of moisture which is taken up by it and this process is accompanied by a change in electronic spin ground state which can be detected by Moessbauer spectroscopy. The sensor is suitable for in-field and industrial application using the recently developed Moessbauer spectrometer MIMOS II. Possible suitability for the detection of moisture in extraterrestrial environments is considered.

  9. On-line determination of moisture in coal and coke

    International Nuclear Information System (INIS)

    Cutmore, N.G.; Sowerby, B.D.

    1987-01-01

    The CSIRO Division of Mineral Engineering is developing various techniques for the on-line determination of moisture in coal and coke, and some instruments are now commercially available. These techniques permit accurate and rapid determination of moisture in materials directly on conveyor belts or in bins. The most promising techniques for direct on-belt measurement of moisture in coal are capacitance and microwave transmission. A non-contacting under-belt capacitance and gamma-ray backscatter technique has determined moisture in coal to better than 0.5 wt% in field tests. CSIRO is developing a fast neutron and gamma-ray transmission technique, which is proving very accurate in laboratory tests. This technique overcomes many of the limitations of thermal neutrons moisture gauges

  10. Initializing numerical weather prediction models with satellite-derived surface soil moisture: Data assimilation experiments with ECMWF's Integrated Forecast System and the TMI soil moisture data set

    Science.gov (United States)

    Drusch, M.

    2007-02-01

    Satellite-derived surface soil moisture data sets are readily available and have been used successfully in hydrological applications. In many operational numerical weather prediction systems the initial soil moisture conditions are analyzed from the modeled background and 2 m temperature and relative humidity. This approach has proven its efficiency to improve surface latent and sensible heat fluxes and consequently the forecast on large geographical domains. However, since soil moisture is not always related to screen level variables, model errors and uncertainties in the forcing data can accumulate in root zone soil moisture. Remotely sensed surface soil moisture is directly linked to the model's uppermost soil layer and therefore is a stronger constraint for the soil moisture analysis. For this study, three data assimilation experiments with the Integrated Forecast System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF) have been performed for the 2-month period of June and July 2002: a control run based on the operational soil moisture analysis, an open loop run with freely evolving soil moisture, and an experimental run incorporating TMI (TRMM Microwave Imager) derived soil moisture over the southern United States. In this experimental run the satellite-derived soil moisture product is introduced through a nudging scheme using 6-hourly increments. Apart from the soil moisture analysis, the system setup reflects the operational forecast configuration including the atmospheric 4D-Var analysis. Soil moisture analyzed in the nudging experiment is the most accurate estimate when compared against in situ observations from the Oklahoma Mesonet. The corresponding forecast for 2 m temperature and relative humidity is almost as accurate as in the control experiment. Furthermore, it is shown that the soil moisture analysis influences local weather parameters including the planetary boundary layer height and cloud coverage.

  11. Development of the neutron technology for measuring the moisture content in China

    International Nuclear Information System (INIS)

    Zhao Jingwu; Liu Shengkang; Zhang Zhiping

    2011-01-01

    According to measuring mode (in-hopper, surface, sampling neutron moisture gauge), the development and application of neutron moisture gauge in china were introduced, which include the following course from only measuring moisture content of soil to monitoring moisture content of farmland and saving water for irrigating farmland, from measuring moisture content of pellet to coke and coal material, from only measuring moisture content to computerized neutron moisture gauges with density compensation and o f high precision. (authors)

  12. Crop yield monitoring in the Sahel using root zone soil moisture anomalies derived from SMOS soil moisture data assimilation

    Science.gov (United States)

    Gibon, François; Pellarin, Thierry; Alhassane, Agali; Traoré, Seydou; Baron, Christian

    2017-04-01

    West Africa is greatly vulnerable, especially in terms of food sustainability. Mainly based on rainfed agriculture, the high variability of the rainy season strongly impacts the crop production driven by the soil water availability in the soil. To monitor this water availability, classical methods are based on daily precipitation measurements. However, the raingauge network suffers from the poor network density in Africa (1/10000km2). Alternatively, real-time satellite-derived precipitations can be used, but they are known to suffer from large uncertainties which produce significant error on crop yield estimations. The present study proposes to use root soil moisture rather than precipitation to evaluate crop yield variations. First, a local analysis of the spatiotemporal impact of water deficit on millet crop production in Niger was done, from in-situ soil moisture measurements (AMMA-CATCH/OZCAR (French Critical Zone exploration network)) and in-situ millet yield survey. Crop yield measurements were obtained for 10 villages located in the Niamey region from 2005 to 2012. The mean production (over 8 years) is 690 kg/ha, and ranges from 381 to 872 kg/ha during this period. Various statistical relationships based on soil moisture estimates were tested, and the most promising one (R>0.9) linked the 30-cm soil moisture anomalies from mid-August to mid-September (grain filling period) to the crop yield anomalies. Based on this local study, it was proposed to derive regional statistical relationships using 30-cm soil moisture maps over West Africa. The selected approach was to use a simple hydrological model, the Antecedent Precipitation Index (API), forced by real-time satellite-based precipitation (CMORPH, PERSIANN, TRMM3B42). To reduce uncertainties related to the quality of real-time rainfall satellite products, SMOS soil moisture measurements were assimilated into the API model through a Particular Filter algorithm. Then, obtained soil moisture anomalies were

  13. CPAC moisture study: Phase 1 report on the study of optical spectra calibration for moisture

    International Nuclear Information System (INIS)

    Veltkamp, D.

    1993-01-01

    This report discusses work done to investigate the feasibility of using optical spectroscopic methods, combined with multivariate Partial Least Squares (PLS) calibration modeling, to quantitatively predict the moisture content of the crust material in Hanford's waste tank materials. Experiments were conducted with BY-104 simulant material for the 400--1100 nm (VIS), 1100--2500 (NIR), and 400-4000 cm -1 (IR) optical regions. The test data indicated that the NIR optical region, with a single PLS calibration factor, provided the highest accuracy response (better than 0.5 wt %) over a 0--25 wt % moisture range. Issues relating to the preparation of moisture samples with the BY-104 materials and the potential implementation within hot cell and waste tanks are also discussed. The investigation of potential material interferences, including physical and chemical properties, and the scaled demonstration of fiber optic and camera types of applications with simulated waste tanks are outlined as future work tasks

  14. Moisture related test protocols for HVS testing

    CSIR Research Space (South Africa)

    Denneman, E

    2008-10-01

    Full Text Available outcomes of HVS tests where the moisture condition of the pavement or specific layers in the pavement is under investigation for a specific test. Practical guidance is then provided on the potential systems (how to manage the moisture – hardware) as well...

  15. Microwave moisture meter for in-shell almonds.

    Science.gov (United States)

    Determining almond kernel moisture content while still in the shell is important for both almond growers and processors. A dielectric method was developed for almond kernel moisture determination from dielectric measurements on in-shell almonds at a single microwave frequency. A sample holder was fi...

  16. Coal Moisture Estimation in Power Plant Mills

    DEFF Research Database (Denmark)

    Andersen, Palle; Bendtsen, Jan Dimon; Pedersen, Tom S.

    2009-01-01

    Knowledge of moisture content in raw coal feed to a power plant coal mill is of importance for efficient operation of the mill. The moisture is commonly measured approximately once a day using offline chemical analysis methods; however, it would be advantageous for the dynamic operation...... of the plant if an on-line estimate were available. In this paper we such propose an on-line estimator (an extended Kalman filter) that uses only existing measurements. The scheme is tested on actual coal mill data collected during a one-month operating period, and it is found that the daily measured moisture...

  17. Estimation of Moisture Content in Coal in Coal Mills

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Mataji, B.

    the moisture content of the coal is proposed based on a simple dynamic energy model of a coal mill, which pulverizes and dries the coal before it is burned in the boiler. An optimal unknown input observer is designed to estimate the moisture content based on an energy balance model. The designed moisture...

  18. Estimation of Moisture Content in Coal in Coal Mills

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Mataji, Babak

    2006-01-01

    the moisture content of the coal is proposed based on a simple dynamic energy model of a coal mill, which pulverizes and dries the coal before it is burned in the boiler. An optimal unknown input observer is designed to estimate the moisture content based on an energy balance model. The designed moisture...

  19. Revealing Invisible Water: Moisture Recycling as an Ecosystem Service.

    Science.gov (United States)

    Keys, Patrick W; Wang-Erlandsson, Lan; Gordon, Line J

    2016-01-01

    An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results into a generalized

  20. Drought monitoring with soil moisture active passive (SMAP) measurements

    Science.gov (United States)

    Mishra, Ashok; Vu, Tue; Veettil, Anoop Valiya; Entekhabi, Dara

    2017-09-01

    Recent launch of space-borne systems to estimate surface soil moisture may expand the capability to map soil moisture deficit and drought with global coverage. In this study, we use Soil Moisture Active Passive (SMAP) soil moisture geophysical retrieval products from passive L-band radiometer to evaluate its applicability to forming agricultural drought indices. Agricultural drought is quantified using the Soil Water Deficit Index (SWDI) based on SMAP and soil properties (field capacity and available water content) information. The soil properties are computed using pedo-transfer function with soil characteristics derived from Harmonized World Soil Database. The SMAP soil moisture product needs to be rescaled to be compatible with the soil parameters derived from the in situ stations. In most locations, the rescaled SMAP information captured the dynamics of in situ soil moisture well and shows the expected lag between accumulations of precipitation and delayed increased in surface soil moisture. However, the SMAP soil moisture itself does not reveal the drought information. Therefore, the SMAP based SWDI (SMAP_SWDI) was computed to improve agriculture drought monitoring by using the latest soil moisture retrieval satellite technology. The formulation of SWDI does not depend on longer data and it will overcome the limited (short) length of SMAP data for agricultural drought studies. The SMAP_SWDI is further compared with in situ Atmospheric Water Deficit (AWD) Index. The comparison shows close agreement between SMAP_SWDI and AWD in drought monitoring over Contiguous United States (CONUS), especially in terms of drought characteristics. The SMAP_SWDI was used to construct drought maps for CONUS and compared with well-known drought indices, such as, AWD, Palmer Z-Index, sc-PDSI and SPEI. Overall the SMAP_SWDI is an effective agricultural drought indicator and it provides continuity and introduces new spatial mapping capability for drought monitoring. As an

  1. A soil moisture-rainfall feedback mechanism. 1. Theory and observations

    International Nuclear Information System (INIS)

    Eltahir, E.A.B.

    1998-01-01

    This paper presents a hypothesis regarding the fundamental role of soil moisture conditions in land-atmosphere interactions. We propose that wet soil moisture conditions over any large region should be associated with relatively large boundary layer moist static energy, which favors the occurrence of more rainfall. Since soil moisture conditions themselves reflect past occurrence of rainfall, the proposed hypothesis implies a positive feedback mechanism between soil moisture and rainfall. This mechanism is based on considerations of the energy balance at the land-atmosphere boundary, in contrast to similar mechanisms that were proposed in the past and that were based on the concepts of water balance and precipitation recycling. The control of soil moisture on surface albedo and Bowen ratio is the fundamental basis of the proposed soil moisture-rainfall feedback mechanism. The water content in the upper soil layer affects these two important properties of the land surface such that both variables decrease with any increase in the water content of the top soil layer. The direct effect of soil moisture on surface albedo implies that wet soil moisture conditions enhance net solar radiation. The direct effect of soil moisture on Bowen ratio dictates that wet soil moisture conditions would tend to enhance net terrestrial radiation at the surface through cooling of surface temperature, reduction of upwards emissions of terrestrial radiation, and simultaneous increase in atmospheric water vapor content and downwards flux of terrestrial radiation. Thus, under wet soil moisture conditions, both components of net radiation are enhanced, resulting in a larger total flux of heat from the surface into the boundary layer. This total flux represents the sum of the corresponding sensible and latent heat fluxes. Simultaneously, cooling of surface temperature should be associated with a smaller sensible heat flux and a smaller depth of the boundary layer

  2. Integrated Heat Air & Moisture Modeling and control

    NARCIS (Netherlands)

    Schijndel, van A.W.M.

    2007-01-01

    The paper presents a recently developed Heat Air & Moisture Laboratory in SimuLink. The simulation laboratory facilitates the integration of the following models: (1) a whole building model; (2) Heating Venting and Air-Conditioning and primary systems; (3) 2D indoor airflow, 3D Heat Air & Moisture

  3. Microwave bale moisture sensing: Field trial continued

    Science.gov (United States)

    A microwave moisture measurement technique was developed at the USDA, ARS Cotton Production and Processing Research Unit for moisture sensing of cotton bales after the bale press. The technique measures the propagation delay of a microwave signal that is transmitted through the cotton bale. This res...

  4. Acoustic and adsorption properties of submerged wood

    Science.gov (United States)

    Hilde, Calvin Patrick

    Wood is a common material for the manufacture of many products. Submerged wood, in particular, is used in niche markets, such as the creation of musical instruments. An initial study performed on submerged wood from Ootsa Lake, British Columbia, provided results that showed that the wood was not suitable for musical instruments. This thesis re-examined the submerged wood samples. After allowing the wood to age unabated in a laboratory setting, the wood was retested under the hypothesis that the physical acoustic characteristics would improve. It was shown, however, that the acoustic properties became less adequate after being left to sit. The adsorption properties of the submerged wood were examined to show that the submerged wood had a larger accessible area of wood than that of control wood samples. This implied a lower amount of crystalline area within the submerged wood. From the combined adsorption and acoustic data for the submerged wood, relationships between the moisture content and speed of sound were created and combined with previous research to create a proposed model to describe how the speed of sound varies with temperature, moisture content and the moisture content corresponding to complete hydration of sorption sites within the wood.

  5. An introduction to NH-A neutron earth base moisture gage

    International Nuclear Information System (INIS)

    Zhu Huaian; Jiang Yulan; Yin Xilin; Yu Peiying; Luo Pinjie

    1988-01-01

    NH-A neutron earth base moisture gage is an accurate instrument which can measure earth moisture rapidly and non-destructively and display moisture results immediately. The deviation is estimated at ±0.012g/cm

  6. Using high-resolution soil moisture modelling to assess the uncertainty of microwave remotely sensed soil moisture products at the correct spatial and temporal support

    NARCIS (Netherlands)

    Wanders, N.; Karssenberg, D.; Bierkens, M. F. P.; Van Dam, J. C.; De Jong, S. M.

    Soil moisture is a key variable in the hydrological cycle and important in hydrological modelling. When assimilating soil moisture into flood forecasting models, the improvement of forecasting skills depends on the ability to accurately estimate the spatial and temporal patterns of soil moisture

  7. Use of Ultrasonic Technology for Soil Moisture Measurement

    Science.gov (United States)

    Choi, J.; Metzl, R.; Aggarwal, M. D.; Belisle, W.; Coleman, T.

    1997-01-01

    In an effort to improve existing soil moisture measurement techniques or find new techniques using physics principles, a new technique is presented in this paper using ultrasonic techniques. It has been found that ultrasonic velocity changes as the moisture content changes. Preliminary values of velocities are 676.1 m/s in dry soil and 356.8 m/s in 100% moist soils. Intermediate values can be calibrated to give exact values for the moisture content in an unknown sample.

  8. Calibration of quantitative neutron radiography method for moisture measurement

    International Nuclear Information System (INIS)

    Nemec, T.; Jeraj, R.

    1999-01-01

    Quantitative measurements of moisture and hydrogenous matter in building materials by neutron radiography (NR) are regularly performed at TRIGA Mark II research of 'Jozef Stefan' Institute in Ljubljana. Calibration of quantitative method is performed using standard brick samples with known moisture content and also with a secondary standard, plexiglas step wedge. In general, the contribution of scattered neutrons to the neutron image is not determined explicitly what introduces an error to the measured signal. Influence of scattered neutrons is significant in regions with high gradients of moisture concentrations, where the build up of scattered neutrons causes distortion of the moisture concentration profile. In this paper detailed analysis of validity of our calibration method for different geometrical parameters is presented. The error in the measured hydrogen concentration is evaluated by an experiment and compared with results obtained by Monte Carlo calculation with computer code MCNP 4B. Optimal conditions are determined for quantitative moisture measurements in order to minimize the error due to scattered neutrons. The method is tested on concrete samples with high moisture content.(author)

  9. A simplified model of saltcake moisture distribution. Letter report

    International Nuclear Information System (INIS)

    Simmons, C.S.

    1995-09-01

    This letter report describes the formulation of a simplified model for finding the moisture distribution in a saltcake waste profile that has been stabilized by pumping out the drainable interstitial liquid. The model is based on assuming that capillarity mainly governs the distribution of moisture in the porous saltcake waste. A stead upward flow of moisture driven by evaporation from the waste surface is conceptualized to occur for isothermal conditions. To obtain hydraulic parameters for unsaturated conditions, the model is calibrated or matched to the relative saturation distribution as measured by neutron probe scans. The model is demonstrated on Tanks 104-BY and 105-TX as examples. A value of the model is that it identifies the key physical parameters that control the surface moisture content in a waste profile. Moreover, the model can be used to estimate the brine application rate at the waste surface that would raise the moisture content there to a safe level. Thus, the model can be applied to help design a strategy for correcting the moisture conditions in a saltcake waste tank

  10. Moisture transport over the brick/mortar interface

    NARCIS (Netherlands)

    Brocken, H.J.P.; Pel, L.

    1995-01-01

    The moisture transport in brick, mortar that was cured separately, and combined brick/mortar samples was studied using NMR. The experimental results show that the mortar is less permeable if it is cured bonded to the brick instead of cured separately. Models of the moisture transport are usually

  11. Reliability and service life of wood structures and buildings

    OpenAIRE

    Zdeňka Havířová; Pavel Kubů

    2005-01-01

    Service life of constructions and buildings of wood is dependent on temperature and moisture conditions in layers of the building cladding where the wood framework is built in. Temperature/moisture conditions or the corresponding equilibrium moisture content (EMC) of the construction show considerable effects on the functional reliability of the whole building from the viewpoint of mechanical resistance and stability (ER1), energy savings and thermal protection (ER6) and hygiene, health and e...

  12. Soil-moisture transport in arid site vadose zones

    International Nuclear Information System (INIS)

    Isaacson, R.E.; Brownell, L.E.; Nelson, R.W.; Roetman, E.L.

    1974-01-01

    Soil-moisture transport processes in the arid soils of the United States Atomic Energy Commission's Hanford site are being evaluated. The depth of penetration of meteoric precipitation has been determined by profiling fall-out tritium at two locations where the water table is about 90 m below ground surface. In situ temperatures and water potentials were measured with temperature transducers and thermocouple psychrometers at the same location to obtain thermodynamic data for identifying the factors influencing soil-moisture transport. Neutron probes are being used to monitor soil-moisture changes in two lysimeters, three metres in diameter by 20 metres deep. The lysimeters are also equipped to measure pressure, temperature and relative humidity as a function of depth and time. Theoretical models based on conservation of momentum expressions are being developed to analyse non-isothermal soil-moisture transport processes. Future work will be concerned with combining the theoretical and experimental work and determining the amount of rainfall required to cause migration of soil-moisture to the water table. (author)

  13. Evaluation of a Soil Moisture Data Assimilation System Over West Africa

    Science.gov (United States)

    Bolten, J. D.; Crow, W.; Zhan, X.; Jackson, T.; Reynolds, C.

    2009-05-01

    A crucial requirement of global crop yield forecasts by the U.S. Department of Agriculture (USDA) International Production Assessment Division (IPAD) is the regional characterization of surface and sub-surface soil moisture. However, due to the spatial heterogeneity and dynamic nature of precipitation events and resulting soil moisture, accurate estimation of regional land surface-atmosphere interactions based sparse ground measurements is difficult. IPAD estimates global soil moisture using daily estimates of minimum and maximum temperature and precipitation applied to a modified Palmer two-layer soil moisture model which calculates the daily amount of soil moisture withdrawn by evapotranspiration and replenished by precipitation. We attempt to improve upon the existing system by applying an Ensemble Kalman filter (EnKF) data assimilation system to integrate surface soil moisture retrievals from the NASA Advanced Microwave Scanning Radiometer (AMSR-E) into the USDA soil moisture model. This work aims at evaluating the utility of merging satellite-retrieved soil moisture estimates with the IPAD two-layer soil moisture model used within the DBMS. We present a quantitative analysis of the assimilated soil moisture product over West Africa (9°N- 20°N; 20°W-20°E). This region contains many key agricultural areas and has a high agro- meteorological gradient from desert and semi-arid vegetation in the North, to grassland, trees and crops in the South, thus providing an ideal location for evaluating the assimilated soil moisture product over multiple land cover types and conditions. A data denial experimental approach is utilized to isolate the added utility of integrating remotely-sensed soil moisture by comparing assimilated soil moisture results obtained using (relatively) low-quality precipitation products obtained from real-time satellite imagery to baseline model runs forced with higher quality rainfall. An analysis of root-zone anomalies for each model

  14. Measured moisture in buildings and adverse health effects: a review.

    Science.gov (United States)

    Mendell, Mark J; Macher, Janet M; Kumagai, Kazukiyo

    2018-04-23

    It has not yet been possible to quantify dose-related health risks attributable to indoor dampness or mold (D/M), to support the setting of health-related limits for D/M. An overlooked target for assessing D/M is moisture in building materials, the critical factor allowing microbial growth. A search for studies of quantified building moisture and occupant health effects identified three eligible studies. Two studies assessed associations between measured wall moisture content and respiratory health in the UK. Both reported dose-related increases in asthma exacerbation with higher measured moisture, with one study reporting an adjusted odds ratio (OR) of 7.0 for night-time asthma symptoms with higher bedroom moisture. The third study assessed relationships between infrared camera-determined wall moisture and atopic dermatitis in South Korea, reporting an adjusted OR of 14.5 for water-damaged homes and moderate or severe atopic dermatitis. Measuring building moisture has, despite extremely limited available findings, potential promise for detecting unhealthy D/M in homes and merits more research attention. Further research to validate these findings should include measured "water activity," which directly assesses moisture availability for microbial growth. Ultimately, evidence-based, health-related thresholds for building moisture, across specific materials and measurement devices, could better guide assessment and remediation of D/M in buildings. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  15. Influence of moisture content on radon diffusion in soil

    International Nuclear Information System (INIS)

    Singh, M.; Ramola, R.C.; Singh, S.; Virk, H.S.

    1990-01-01

    Radon diffusion from soil has been studied as a function of the moisture content of the soil. A few simple experiments showed that up to a certain moisture content the radon diffusion increased with increasing moisture. A sharp rise in radon concentration occurred as the moisture was increased from the completely dry state to 13% water by weight. The radon flux was measured for columns of dry, moist and water saturated soil. The highest flux came from the column filled with moist soil. Water saturated soil gave the lowest flux because of the much lower diffusion coefficient of radon through water. (author)

  16. Soil moisture effects during bioventing in fuel-contaminated arid soils

    International Nuclear Information System (INIS)

    Zwick, T.C.; Leeson, A.; Hinchee, R.E.; Hoeppel, R.E.; Bowling, L.

    1995-01-01

    This study evaluated the effects of soil moisture addition on microbial activity during bioventing of dry, sandy soils at the Marine Corps Air Ground Combat Center (MCAGCC), Twentynine Palms, California. Soils at the site have been contaminated to a depth of approximately 80 ft (24 m) with gasoline, JP-5 jet fuel, and diesel fuel. Based on the low soil moisture measured at the site (2 to 3% by weight), it was determined that soil moisture may be limiting biodegradation. To evaluate the effect that moisture addition had on microbial activity under field conditions, a subsurface drip irrigation system was installed above the fuel hydrocarbon plume. Irrigation water was obtained from two monitoring wells on the site, where groundwater was approximately 192 ft (59 m) below ground surface. Advancement of the wetting front was monitored. In situ respiration rates increased significantly after moisture addition. The results of this study provide evidence for the potential applicability of moisture addition in conjunction with bioventing for site remediation in arid environments. Further work is planned to investigate optimization of moisture addition

  17. 24 CFR 3285.204 - Ground moisture control.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Ground moisture control. 3285.204 Section 3285.204 Housing and Urban Development Regulations Relating to Housing and Urban Development... moisture control. (a) Vapor retarder. If the space under the home is to be enclosed with skirting or other...

  18. Use of passive microwave remote sensing to monitor soil moisture

    International Nuclear Information System (INIS)

    Wigneron, J.P.; Schmugge, T.; Chanzy, A.; Calvet, J.C.; Kerr, Y.

    1998-01-01

    Surface soil moisture is a key variable to describe the water and energy exchanges at the land surface/atmosphere interface. However, soil moisture is highly variable both spatially and temporally. Passive microwave remotely sensed data have great potential for providing estimates of soil moisture with good temporal repetition (on a daily basis) and at regional scale (∼ 10 km). This paper reviews the various methods for remote sensing of soil moisture from microwave radiometric systems. Potential applications from both airborne and spatial observations are discussed in the fields of agronomy, hydrology and meteorology. Emphasis in this paper is given to relatively new aspects of microwave techniques and of temporal soil moisture information analysis. In particular, the aperture synthesis technique allows us now to a address the soil moisture information needs on a global basis, from space instruments. (author) [fr

  19. A Literature Review on the Study of Moisture in Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Trautschold, Olivia Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-25

    This literature review covers the main chemical and physical interactions between moisture and the polymer matrix. Fickian versus Non-Fickian diffusion behaviors are discussed in approximating the characteristics of moisture sorption. Also, bound water and free water sorbed in polymers are distinguished. Methods to distinguish between bound and free water include differential scanning calorimetry, infrared spectroscopy, and time-domain nuclear magnetic resonance spectroscopy. The difference between moisture sorption and water sorption is considered, as well as the difficulties associated with preventing moisture sorption. Furthermore, specific examples of how moisture sorption influences polymers include natural fiber-polymer composites, starch-based biodegradable thermoplastics, and thermoset polyurethane and epoxies.

  20. Diagnosing MJO Destabilization and Propagation with the Moisture and MSE Budgets

    Science.gov (United States)

    Maloney, Eric; Wolding, Brandon

    2015-04-01

    Novel diagnostics obtained as an extension of empirical orthogonal function analysis are used as a composting basis to gain insight into MJO dynamics through examination of reanalysis moisture and moist static energy budgets. The net effect of vertical moisture advection and cloud processes was found to be a modest positive feedback to column moisture anomalies during both enhanced and suppressed phases of the MJO. This positive feedback is regionally strengthened by anomalous surface fluxes of latent heat. The modulation of horizontal synoptic scale eddy mixing acts as a negative feedback to column moisture anomalies, while anomalous winds acting against the mean state moisture gradient aid in eastward propagation. These processes act in a systematic fashion across the Indian Ocean and oceanic regions of the Maritime Continent. The ability to approximately close the MSE budget serves an important role in constraining the moisture budget, whose residual is several times larger than the total and horizontal advective moisture tendencies. Comparison with TRMM precipitation anomalies suggests that the moisture budget residual results from an underestimation by ERAi of variations in both total precipitation and vertical moisture advection associated with the MJO. The results of this study support the concept of the MJO as a moisture-mode. This analysis is extended to examine the impact of boundary layer convergence driven by MJO SST anomalies on the vertically-integrated moisture budget. Results from a coupled version of the SP-CAM suggest that SST-driven moisture convergence anomalies are of a sufficient amplitude to be important for MJO propagation and destabilization, and may help explain why coupled models produce better simulations of the MJO than uncoupled models.

  1. Understanding the bias between moisture content by oven drying and water content by Karl Fischer titration at moisture equilibrium

    Science.gov (United States)

    Multiple causes of the difference between equilibrium moisture and water content have been found. The errors or biases were traced to the oven drying procedure to determine moisture content. The present paper explains the nature of the biases in oven drying and how it is possible to suppress one ...

  2. Optimization on Measurement Method for Neutron Moisture Meter

    International Nuclear Information System (INIS)

    Gong Yalin; Wu Zhiqiang; Li Yanfeng; Wang Wei; Song Qingfeng; Liu Hui; Wei Xiaoyun; Zhao Zhonghua

    2010-01-01

    When the water in the measured material is nonuniformity, the measured results of the neutron moisture meter in the field may have errors, so the measured errors of the moisture meter associated with the water nonuniformity in material were simulated by Monte Carlo method. A new measurement method of moisture meter named 'transmission plus scatter' was put forward. The experiment results show that the new measurement method can reduce the error even if the water in the material is nonuniformity. (authors)

  3. A Novel Bias Correction Method for Soil Moisture and Ocean Salinity (SMOS Soil Moisture: Retrieval Ensembles

    Directory of Open Access Journals (Sweden)

    Ju Hyoung Lee

    2015-12-01

    Full Text Available Bias correction is a very important pre-processing step in satellite data assimilation analysis, as data assimilation itself cannot circumvent satellite biases. We introduce a retrieval algorithm-specific and spatially heterogeneous Instantaneous Field of View (IFOV bias correction method for Soil Moisture and Ocean Salinity (SMOS soil moisture. To the best of our knowledge, this is the first paper to present the probabilistic presentation of SMOS soil moisture using retrieval ensembles. We illustrate that retrieval ensembles effectively mitigated the overestimation problem of SMOS soil moisture arising from brightness temperature errors over West Africa in a computationally efficient way (ensemble size: 12, no time-integration. In contrast, the existing method of Cumulative Distribution Function (CDF matching considerably increased the SMOS biases, due to the limitations of relying on the imperfect reference data. From the validation at two semi-arid sites, Benin (moderately wet and vegetated area and Niger (dry and sandy bare soils, it was shown that the SMOS errors arising from rain and vegetation attenuation were appropriately corrected by ensemble approaches. In Benin, the Root Mean Square Errors (RMSEs decreased from 0.1248 m3/m3 for CDF matching to 0.0678 m3/m3 for the proposed ensemble approach. In Niger, the RMSEs decreased from 0.14 m3/m3 for CDF matching to 0.045 m3/m3 for the ensemble approach.

  4. Automatic moisture content determination on biomass with NIR and radio frequency spectroscopy; Automatisk fukthaltsmaetning paa biobraenslen med NIR samt radiofrekvent spektroskopi

    Energy Technology Data Exchange (ETDEWEB)

    Dahlquist, Erik; Nystroem, Jenny; Thorin, Eva; Paz, Ana de la [Maelardalen Univ. (Sweden). Dept. of Public Technology; Axrup, Lars [Stora Enso AB (Sweden)

    2005-08-01

    The goal with the project has been to evaluate two methods for determination of moisture content in biomass fuels and to determine if these methods can be used in practice in connection with delivery control of biomass at power plants. Tests have been performed with different biomass qualities and with two different measurement methods within a large moisture span, 0.6-72%. The two methods have been NIR (Near Infrared spectroscopy), and RF (Radio Frequency spectroscopy). The NIR-method is a surface analysis method, where hydro-carbons like wood have a different absorption pattern than water. The RF-method is a bulk method and utilizes that wood and water have different dielectric constants. Radio waves thus are affected differently by transportation through wet and dry biomass. In this project we have studied how representative sampling can be achieved from a large volume of delivered biomass fuel. We also have performed calibration with mixtures of the different fuels. Sampling has been performed by extracting biomass in a four meter long screw from the large volume as it is poured into a storage vessel. A conveyor belt is then transporting the material to the measurement systems. Two different NIR-instruments, DA (Diod Array) -NIR respective FT (Fourier Transform)- NIR, were placed above the conveyor belt. The material was collected from the belt into the measuring vessel for the RF, a 200 liter 'oil barrel'. The radio waves were sent from the transceiver into the sample from above without direct contact between the biomass and the transceiver antenna. Six different fuels were studied separately. Calibration was performed where the moisture content was varied by mixing relatively dry fuel with humidified biomass in different proportions a day before the measurements. Samples were taken from each mixture in connection with the measurements, from the conveyor belt. The samples were made in such a way that they represented the whole volume as good as

  5. an intermediate moisture meat

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-04

    Jul 4, 2008 ... traditional SM muscle without compromising quality. ... technique is intermediate moisture food processing. ... Traditionally, most tsire suya producers use ..... quality of Chinese purebred and European X Chinese crossbred ...

  6. Water sorption in wood and modified wood at high values of relative humidity

    DEFF Research Database (Denmark)

    Thygesen, Lisbeth Garbrecht; Engelund, Emil Tang; Hoffmeyer, Preben

    2010-01-01

    additional results corroborate this conclusion: (1) calculation of the theoretical contribution of capillary condensation to the moisture content (MC) in wood based on idealized microstructural geometries by means of the Kelvin and Laplace equations resulted in very small contributions to the equilibrium...... moisture content (EMC), i.e., below 0.35% moisture at 99.9% RH. (2) The ratio between the EMC of acetylated and untreated samples did not show an increasing trend for increasing RH, as would have been the case if capillary condensation had taken place in both untreated and acetylated wood. (3) Low field......, and the pressure plate technique. The curve form for the untreated samples did not show an upward bend, except perhaps above 99.5% RH, indicating that – contrary to what has hitherto been assumed – capillary condensation does not play a significant role for water sorption in wood below fiber saturation. Three...

  7. Assessment of the SMAP Passive Soil Moisture Product

    Science.gov (United States)

    Chan, Steven K.; Bindlish, Rajat; O'Neill, Peggy E.; Njoku, Eni; Jackson, Tom; Colliander, Andreas; Chen, Fan; Burgin, Mariko; Dunbar, Scott; Piepmeier, Jeffrey; hide

    2016-01-01

    The National Aeronautics and Space Administration (NASA) Soil Moisture Active Passive (SMAP) satellite mission was launched on January 31, 2015. The observatory was developed to provide global mapping of high-resolution soil moisture and freeze-thaw state every two to three days using an L-band (active) radar and an L-band (passive) radiometer. After an irrecoverable hardware failure of the radar on July 7, 2015, the radiometer-only soil moisture product became the only operational Level 2 soil moisture product for SMAP. The product provides soil moisture estimates posted on a 36 kilometer Earth-fixed grid produced using brightness temperature observations from descending passes. Within months after the commissioning of the SMAP radiometer, the product was assessed to have attained preliminary (beta) science quality, and data were released to the public for evaluation in September 2015. The product is available from the NASA Distributed Active Archive Center at the National Snow and Ice Data Center. This paper provides a summary of the Level 2 Passive Soil Moisture Product (L2_SM_P) and its validation against in situ ground measurements collected from different data sources. Initial in situ comparisons conducted between March 31, 2015 and October 26, 2015, at a limited number of core validation sites (CVSs) and several hundred sparse network points, indicate that the V-pol Single Channel Algorithm (SCA-V) currently delivers the best performance among algorithms considered for L2_SM_P, based on several metrics. The accuracy of the soil moisture retrievals averaged over the CVSs was 0.038 cubic meter per cubic meter unbiased root-mean-square difference (ubRMSD), which approaches the SMAP mission requirement of 0.040 cubic meter per cubic meter.

  8. Use of digital images to estimate soil moisture

    Directory of Open Access Journals (Sweden)

    João F. C. dos Santos

    Full Text Available ABSTRACT The objective of this study was to analyze the relation between the moisture and the spectral response of the soil to generate prediction models. Samples with different moisture contents were prepared and photographed. The photographs were taken under homogeneous light condition and with previous correction for the white balance of the digital photograph camera. The images were processed for extraction of the median values in the Red, Green and Blue bands of the RGB color space; Hue, Saturation and Value of the HSV color space; and values of the digital numbers of a panchromatic image obtained from the RGB bands. The moisture of the samples was determined with the thermogravimetric method. Regression models were evaluated for each image type: RGB, HSV and panchromatic. It was observed the darkening of the soil with the increase of moisture. For each type of soil, a model with best fit was observed and to use these models for prediction purposes, it is necessary to choose the model with best fit in advance, according to the soil characteristics. Soil moisture estimation as a function of its spectral response by digital image processing proves promising.

  9. Package selection for moisture protection for solid, oral drug products.

    Science.gov (United States)

    Waterman, Kenneth C; MacDonald, Bruce C

    2010-11-01

    This review describes how best to select the appropriate packaging options for solid, oral drug products based on both chemical and physical stability, with respect to moisture protection. This process combines an accounting for the initial moisture content of dosage form components, moisture transfer into (out of) packaging based on a moisture vapor transfer rate (MVTR), and equilibration between drug products and desiccants based on their moisture sorption isotherms to provide an estimate of the instantaneous relative humidity (RH) within the packaging. This time-based RH is calculationally combined with a moisture-sensitive Arrhenius equation (determined using the accelerated stability assessment program, ASAP) to predict the drug product's chemical stability over time as a function of storage conditions and packaging options. While physical stability of dosage forms with respect to moisture has been less well documented, a process is recommended based on the threshold RH at which changes (e.g., dosage form dissolution, tablet hardness, drug form) become problematic. The overall process described allows packaging to be determined for a drug product scientifically, with the effect of any changes to storage conditions or packaging to be explicitly accounted for. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association

  10. Engineering properties of sunflower seed: Effect of dehulling and moisture content

    Directory of Open Access Journals (Sweden)

    Mudasir Ahmad Malik

    2016-12-01

    Full Text Available The study diagnosed engineering properties on varying moisture content of sunflower seed and kernel from 7.6 to 25% (wet basis. On increasing moisture, dimensional values increased for both seed and kernel. Bulk density, true density and porosity were found higher for kernel as compared to seed at each moisture content. On increasing the moisture content from 7.6 to 25%, true density, porosity and thousand kernel weight increased. Coefficient of static friction on plywood was found maximum for kernel at 25% moisture content, while it was minimum for seed on glass at 7.6% moisture content. The angle of repose was maximum for kernel as compared to seed. Initial cracking force, average rupture force and average rupture energy for seed and kernel decreased with an increase in the moisture content. The kernel was found to be more resistant to initial cracking than seed.

  11. Use of moisture probes in building materials industry

    International Nuclear Information System (INIS)

    Hanke, L.

    A neutron probe to be built in the production line was developed for monitoring moisture content of bulk materials and suspensions of all types in the building material industry. The probe is dust- and external moisture-protected. The probe measuring capacity is about 100 l, the mean measurement error is +- 0.008 g water per 1 cm 3 , which for fine sand represents an error of +- 0.3%. The probe is connected via a cable to a measuring instrument showing an electrical value proportional to the measured material moisture content. (Z.M.)

  12. Using lamb waves tomonitor moisture absorption thermally fatigues composite laminates

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Sun; Cho, Youn Ho [School of Mechanical Engineering, Pusan National University, Busan (Korea, Republic of)

    2016-06-15

    Nondestructive evaluation for material health monitoring is important in aerospace industries. Composite laminates are exposed to heat cyclic loading and humid environment depending on flight conditions. Cyclic heat loading and moisture absorption may lead to material degradation such as matrix breaking, debonding, and delamination. In this paper, the moisture absorption ratio was investigated by measuring the Lamb wave velocity. The composite laminates were manufactured and subjected to different thermal aging cycles and moisture absorption. For various conditions of these cycles, not only changes in weight and also ultrasonic wave velocity were measured, and the Lamb wave velocity at various levels of moisture on a carbon-epoxy plate was investigated. Results from the experiment show a linear correlation between moisture absorption ratio and Lamb wave velocity at different thermal fatigue stages. The presented method can be applied as an alternative solution in the online monitoring of composite laminate moisture levels in commercial flights.

  13. Qualitative and quantitative assessment of interior moisture buffering by enclosures

    DEFF Research Database (Denmark)

    Janssen, Hans; Roels, Staf

    2009-01-01

    The significance of interior humidity in attaining sustainable, durable, healthy and comfortable buildings is increasingly recognised. Given their significant interaction, interior humidity appraisals need a qualitative and/or quantitative assessment of interior moisture buffering. While the effe......The significance of interior humidity in attaining sustainable, durable, healthy and comfortable buildings is increasingly recognised. Given their significant interaction, interior humidity appraisals need a qualitative and/or quantitative assessment of interior moisture buffering. While...... the effective moisture penetration depth and effective capacitance models allow quantified assessment, their reliance on the ‘moisture penetration depth’ necessitates comprehensive material properties and hampers their application to multi-dimensional interior objects. On the other hand, while various recently...... an alternative basis for quantitative evaluation of interior moisture buffering by the effective moisture penetration depth and effective capacitance models. The presented methodology uses simple and fast measurements only and can also be applied to multimaterial and/or multidimensional interior elements....

  14. Non-destructive determination of moisture content and micro-fibril angle of wood using a poly-chromatic X-ray beam theoretical and experimental approach; Exploitation d'un rayonnement X poly-energetique pour la determination de la teneur en eau et de l'angle de microfibrilles du bois: approche theorique et experimentale

    Energy Technology Data Exchange (ETDEWEB)

    Baettig, R

    2005-07-15

    Non-destructive determination of moisture content and micro-fibril angle are important stakes for the sciences of the wood because these two parameters influence strongly the macroscopic behavior of the wood. For example, the shrinkage, the mechanical properties, the thermal and acoustic conductivity are dependent on the moisture content and their anisotropic character is largely governed by the micro-fibril angle. We used the light difference between X-ray mass attenuation coefficient for the water and for the wood in transmission. Regrettably, the results show that this difference between X-ray mass attenuation coefficient is insufficient to allow the precise measurement of the moisture content.In spite of this, the coherent scattering shows sensitive effects. So, by using a poly-energetic beam and a spectrometric system, we were able to discriminate between the crystalline constituent (cellulose) of the amorphous constituent (water) in a sample of wet wood, because for a given angle these phases scatter in different energy. Besides, the device created allowed us to study the crystalline phase of the wood. We were able to confront experimental profiles of diffraction with theoretical profiles of diffraction, obtained by means of a rigorous simulation, in the objective to estimate the average micro-fibril angle and its standard deviation. (author)

  15. Moisture availability limits subalpine tree establishment.

    Science.gov (United States)

    Andrus, Robert A; Harvey, Brian J; Rodman, Kyle C; Hart, Sarah J; Veblen, Thomas T

    2018-03-01

    In the absence of broad-scale disturbance, many temperate coniferous forests experience successful seedling establishment only when abundant seed production coincides with favorable climate. Identifying the frequency of past establishment events and the climate conditions favorable for seedling establishment is essential to understanding how climate warming could affect the frequency of future tree establishment events and therefore future forest composition or even persistence of a forest cover. In the southern Rocky Mountains, USA, research on the sensitivity of establishment of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa)-two widely distributed, co-occurring conifers in North America-to climate variability has focused on the alpine treeline ecotone, leaving uncertainty about the sensitivity of these species across much of their elevation distribution. We compared annual germination dates for >450 Engelmann spruce and >500 subalpine fir seedlings collected across a complex topographic-moisture gradient to climate variability in the Colorado Front Range. We found that Engelmann spruce and subalpine fir established episodically with strong synchrony in establishment events across the study area. Broad-scale establishment events occurred in years of high soil moisture availability, which were characterized by above-average snowpack and/or cool and wet summer climatic conditions. In the recent half of the study period (1975-2010), a decrease in the number of fir and spruce establishment events across their distribution coincided with declining snowpack and a multi-decadal trend of rising summer temperature and increasing moisture deficits. Counter to expected and observed increases in tree establishment with climate warming in maritime subalpine forests, our results show that recruitment declines will likely occur across the core of moisture-limited subalpine tree ranges as warming drives increased moisture deficits. © 2018 by the

  16. Performance of a rigid and a flexible adhesive in lumber joints subjected to moisture content changes

    Science.gov (United States)

    G. P. Krueger; R. F. Blomquist

    1964-01-01

    Experimental work was undertaken to investigate the extent and magnitude of deterioration that can occur in typical plywood-to-lumber glue joints subjected to stresses resulting from changes in the moisture content of the wood, and to compare the performance of a somewhat flexible or deformable adhesive to that of a rigid adhesive in these joints. Results showed that...

  17. EDITORIAL: Microwave Moisture Measurements

    Science.gov (United States)

    Kaatze, Udo; Kupfer, Klaus; Hübner, Christof

    2007-04-01

    Microwave moisture measurements refer to a methodology by which the water content of materials is non-invasively determined using electromagnetic fields of radio and microwave frequencies. Being the omnipresent liquid on our planet, water occurs as a component in most materials and often exercises a significant influence on their properties. Precise measurements of the water content are thus extremely useful in pure sciences, particularly in biochemistry and biophysics. They are likewise important in many agricultural, technical and industrial fields. Applications are broad and diverse, and include the quality assessment of foodstuffs, the determination of water content in paper, cardboard and textile production, the monitoring of moisture in sands, gravels, soils and constructions, as well as the measurement of water admixtures to coal and crude oil in reservoirs and in pipelines. Microwave moisture measurements and evaluations require insights in various disciplines, such as materials science, dielectrics, the physical chemistry of water, electrodynamics and microwave techniques. The cooperation of experts from the different fields of science is thus necessary for the efficient development of this complex discipline. In order to advance cooperation the Workshop on Electromagnetic Wave Interaction with Water and Moist Substances was held in 1993 in Atlanta. It initiated a series of international conferences, of which the last one was held in 2005 in Weimar. The meeting brought together 130 scientists and engineers from all over the world. This special issue presents a collection of some selected papers that were given at the event. The papers cover most topics of the conference, featuring dielectric properties of aqueous materials, electromagnetic wave interactions, measurement methods and sensors, and various applications. The special issue is dedicated to Dr Andrzej W Kraszewski, who died in July 2006 after a distinguished career of 48 years in the research of

  18. Autoradiographic study on moisture distribution in pearl-barley and in rice grain

    International Nuclear Information System (INIS)

    Sakharov, Eh.V.; Koz'mina, E.P.; Troitskaya, E.Ya

    1975-01-01

    The dependence of some structural details of the pearl-barley and rice endosperm on the internal moisture distribution is found. The general scheme of the study is shown. The curves of the local moisture distribution in the pearly-barley and rice kernel are plotted according to the radiography data. Moisture distribution over the whole section of the rice kernel is relatively constant at 85 deg C after ten minutes of moisture. Whereas moisture of pearl-barley kernel is only approaching the center of kernel by the time the moisture content increases to 1.5-2%. The slow moisture transfer in the pearl-barley kernel makes the cooking period three times longer as that of the rice

  19. 30 CFR 27.41 - Test to determine resistance to moisture.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Test to determine resistance to moisture. 27.41... determine resistance to moisture. Components, subassemblies, or assemblies, the normal functioning of which might be affected by moisture, shall be tested in atmospheres of high relative humidity (80 percent or...

  20. Creating soil moisture maps based on radar satellite imagery

    Science.gov (United States)

    Hnatushenko, Volodymyr; Garkusha, Igor; Vasyliev, Volodymyr

    2017-10-01

    The presented work is related to a study of mapping soil moisture basing on radar data from Sentinel-1 and a test of adequacy of the models constructed on the basis of data obtained from alternative sources. Radar signals are reflected from the ground differently, depending on its properties. In radar images obtained, for example, in the C band of the electromagnetic spectrum, soils saturated with moisture usually appear in dark tones. Although, at first glance, the problem of constructing moisture maps basing on radar data seems intuitively clear, its implementation on the basis of the Sentinel-1 data on an industrial scale and in the public domain is not yet available. In the process of mapping, for verification of the results, measurements of soil moisture obtained from logs of the network of climate stations NOAA US Climate Reference Network (USCRN) were used. This network covers almost the entire territory of the United States. The passive microwave radiometers of Aqua and SMAP satellites data are used for comparing processing. In addition, other supplementary cartographic materials were used, such as maps of soil types and ready moisture maps. The paper presents a comparison of the effect of the use of certain methods of roughening the quality of radar data on the result of mapping moisture. Regression models were constructed showing dependence of backscatter coefficient values Sigma0 for calibrated radar data of different spatial resolution obtained at different times on soil moisture values. The obtained soil moisture maps of the territories of research, as well as the conceptual solutions about automation of operations of constructing such digital maps, are presented. The comparative assessment of the time required for processing a given set of radar scenes with the developed tools and with the ESA SNAP product was carried out.

  1. In-situ determination of moisture in road pavement by nuclear methods

    International Nuclear Information System (INIS)

    Gray, G.W.; Sowerby, B.D.; Youdale, G.P.

    1981-04-01

    The use of neutron moisture probes to determine moisture in compacted pavement layers has been studied on samples representative of those used by the New South Wales Department of Main Roads for roadway construction. The aim of this work was to measure the average moisture content of the upper layer (15-20 cm thick) with minimum interference from moisture in underlying layers. Sub-surface probes using high (α-Be) and low (α-Li) energy neutron sources were examined; conventional α-Be sources in specially designed compact probes should result in an error due to base moisture and density variations of less than 0.4 wt % moisture. As this error is probably less than those due to sampling and geometry variations in the field, such a probe should be sufficiently accurate for DMR requirements. If less sensitivity to base moisture is required, the α-Li source will reduce this sensitivity by a factor of about 1.4

  2. Development of density and moisture gauge by nuclear techniques

    International Nuclear Information System (INIS)

    Mangelaviraj, V.; Karasuddhi, P.; Banchornthevakal, V.; Punyachaiya, S.

    1981-08-01

    A combined soil moisture/density gauge using nuclear technique was developed. Simultaneous density and moisture measurements can take place by means of gamma and neutron sources which are attached to the moisture probe. Backscattered gamma radiation giving information on density is detected by a G.M. counter while slow neutron radiation containing moisture information is detected by a boron-lined proportional counter. The instrument makes use of a 30 mCi americium 241-beryllium neutron source and a 10 mCi cesium 137 gamma source. The instrument was calibrated using soil and sand filled in a 200 litre-barrel in laboratory and field work which was carried out to check the correctness of the calibration curves. (author)

  3. Moisture dependence of radon transport in concrete : Measurements and modeling

    NARCIS (Netherlands)

    Cozmuta, [No Value; van der Graaf, ER; de Meijer, RJ

    2003-01-01

    The moisture dependence of the radon-release rate of concrete was measured under well controlled conditions. It was found that the radon-release rate almost linearly increases up to moisture contents of 50 to 60%. At 70 to 80% a maximum was found and for higher moisture contents the radon-release

  4. An integrated GIS application system for soil moisture data assimilation

    Science.gov (United States)

    Wang, Di; Shen, Runping; Huang, Xiaolong; Shi, Chunxiang

    2014-11-01

    The gaps in knowledge and existing challenges in precisely describing the land surface process make it critical to represent the massive soil moisture data visually and mine the data for further research.This article introduces a comprehensive soil moisture assimilation data analysis system, which is instructed by tools of C#, IDL, ArcSDE, Visual Studio 2008 and SQL Server 2005. The system provides integrated service, management of efficient graphics visualization and analysis of land surface data assimilation. The system is not only able to improve the efficiency of data assimilation management, but also comprehensively integrate the data processing and analysis tools into GIS development environment. So analyzing the soil moisture assimilation data and accomplishing GIS spatial analysis can be realized in the same system. This system provides basic GIS map functions, massive data process and soil moisture products analysis etc. Besides,it takes full advantage of a spatial data engine called ArcSDE to effeciently manage, retrieve and store all kinds of data. In the system, characteristics of temporal and spatial pattern of soil moiture will be plotted. By analyzing the soil moisture impact factors, it is possible to acquire the correlation coefficients between soil moisture value and its every single impact factor. Daily and monthly comparative analysis of soil moisture products among observations, simulation results and assimilations can be made in this system to display the different trends of these products. Furthermore, soil moisture map production function is realized for business application.

  5. Congo Basin precipitation: Assessing seasonality, regional interactions, and sources of moisture

    Science.gov (United States)

    Dyer, Ellen L. E.; Jones, Dylan B. A.; Nusbaumer, Jesse; Li, Harry; Collins, Owen; Vettoretti, Guido; Noone, David

    2017-07-01

    Precipitation in the Congo Basin was examined using a version of the National Center for Atmospheric Research Community Earth System Model (CESM) with water tagging capability. Using regionally defined water tracers, or tags, the moisture contribution from different source regions to Congo Basin precipitation was investigated. We found that the Indian Ocean and evaporation from the Congo Basin were the dominant moisture sources and that the Atlantic Ocean was a comparatively small source of moisture. In both rainy seasons the southwestern Indian Ocean contributed about 21% of the moisture, while the recycling ratio for moisture from the Congo Basin was about 25%. Near the surface, a great deal of moisture is transported from the Atlantic into the Congo Basin, but much of this moisture is recirculated back over the Atlantic in the lower troposphere. Although the southwestern Indian Ocean is a major source of Indian Ocean moisture, it is not associated with the bulk of the variability in precipitation over the Congo Basin. In wet years, more of the precipitation in the Congo Basin is derived from Indian Ocean moisture, but the spatial distribution of the dominant sources is shifted, reflecting changes in the midtropospheric circulation over the Indian Ocean. During wet years there is increased transport of moisture from the equatorial and eastern Indian Ocean. Our results suggest that reliably capturing the linkages between the large-scale circulation patterns over the Indian Ocean and the local circulation over the Congo Basin is critical for future projections of Congo Basin precipitation.

  6. Propagation of soil moisture memory to streamflow and evapotranspiration in Europe

    Science.gov (United States)

    Orth, R.; Seneviratne, S. I.

    2013-10-01

    As a key variable of the land-climate system soil moisture is a main driver of streamflow and evapotranspiration under certain conditions. Soil moisture furthermore exhibits outstanding memory (persistence) characteristics. Many studies also report distinct low frequency variations for streamflow, which are likely related to soil moisture memory. Using data from over 100 near-natural catchments located across Europe, we investigate in this study the connection between soil moisture memory and the respective memory of streamflow and evapotranspiration on different time scales. For this purpose we use a simple water balance model in which dependencies of runoff (normalised by precipitation) and evapotranspiration (normalised by radiation) on soil moisture are fitted using streamflow observations. The model therefore allows us to compute the memory characteristics of soil moisture, streamflow and evapotranspiration on the catchment scale. We find considerable memory in soil moisture and streamflow in many parts of the continent, and evapotranspiration also displays some memory at monthly time scale in some catchments. We show that the memory of streamflow and evapotranspiration jointly depend on soil moisture memory and on the strength of the coupling of streamflow and evapotranspiration to soil moisture. Furthermore, we find that the coupling strengths of streamflow and evapotranspiration to soil moisture depend on the shape of the fitted dependencies and on the variance of the meteorological forcing. To better interpret the magnitude of the respective memories across Europe, we finally provide a new perspective on hydrological memory by relating it to the mean duration required to recover from anomalies exceeding a certain threshold.

  7. Propagation of soil moisture memory to streamflow and evapotranspiration in Europe

    Directory of Open Access Journals (Sweden)

    R. Orth

    2013-10-01

    Full Text Available As a key variable of the land-climate system soil moisture is a main driver of streamflow and evapotranspiration under certain conditions. Soil moisture furthermore exhibits outstanding memory (persistence characteristics. Many studies also report distinct low frequency variations for streamflow, which are likely related to soil moisture memory. Using data from over 100 near-natural catchments located across Europe, we investigate in this study the connection between soil moisture memory and the respective memory of streamflow and evapotranspiration on different time scales. For this purpose we use a simple water balance model in which dependencies of runoff (normalised by precipitation and evapotranspiration (normalised by radiation on soil moisture are fitted using streamflow observations. The model therefore allows us to compute the memory characteristics of soil moisture, streamflow and evapotranspiration on the catchment scale. We find considerable memory in soil moisture and streamflow in many parts of the continent, and evapotranspiration also displays some memory at monthly time scale in some catchments. We show that the memory of streamflow and evapotranspiration jointly depend on soil moisture memory and on the strength of the coupling of streamflow and evapotranspiration to soil moisture. Furthermore, we find that the coupling strengths of streamflow and evapotranspiration to soil moisture depend on the shape of the fitted dependencies and on the variance of the meteorological forcing. To better interpret the magnitude of the respective memories across Europe, we finally provide a new perspective on hydrological memory by relating it to the mean duration required to recover from anomalies exceeding a certain threshold.

  8. Behavior of an epoxy-polysulfide adhesive in wood joints exposed to moisture content changes

    Science.gov (United States)

    Gordon P. Krueger

    1965-01-01

    The mechanical behavior of a flexible epoxy-resin adhesive system was observed in joints of plywood to lumber. The joints were subjected to internal swelling stresses caused by an increase in moisture content. Previous experimental work at the U.S. Forest Products Laboratory has shown that this adhesive system acts as a strain-absorbing cushion and thus has a...

  9. The Contribution of Soil Moisture Information to Forecast Skill: Two Studies

    Science.gov (United States)

    Koster, Randal

    2010-01-01

    This talk briefly describes two recent studies on the impact of soil moisture information on hydrological and meteorological prediction. While the studies utilize soil moisture derived from the integration of large-scale land surface models with observations-based meteorological data, the results directly illustrate the potential usefulness of satellite-derived soil moisture information (e.g., from SMOS and SMAP) for applications in prediction. The first study, the GEWEX- and ClIVAR-sponsored GLACE-2 project, quantifies the contribution of realistic soil moisture initialization to skill in subseasonal forecasts of precipitation and air temperature (out to two months). The multi-model study shows that soil moisture information does indeed contribute skill to the forecasts, particularly for air temperature, and particularly when the initial local soil moisture anomaly is large. Furthermore, the skill contributions tend to be larger where the soil moisture initialization is more accurate, as measured by the density of the observational network contributing to the initialization. The second study focuses on streamflow prediction. The relative contributions of snow and soil moisture initialization to skill in streamflow prediction at seasonal lead, in the absence of knowledge of meteorological anomalies during the forecast period, were quantified with several land surface models using uniquely designed numerical experiments and naturalized streamflow data covering mUltiple decades over the western United States. In several basins, accurate soil moisture initialization is found to contribute significant levels of predictive skill. Depending on the date of forecast issue, the contributions can be significant out to leads of six months. Both studies suggest that improvements in soil moisture initialization would lead to increases in predictive skill. The relevance of SMOS and SMAP satellite-based soil moisture information to prediction are discussed in the context of these

  10. Moisture Durability with Vapor-Permeable Insulating Sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Lepage, R. [Building Science Corporation, Somerville, MA (United States); Lstiburek, J. [Building Science Corporation, Somerville, MA (United States)

    2013-09-01

    Exterior sheathing insulation is an effective strategy in increasing the overall R-value of wall assemblies; other benefits include decreasing the effects of thermal bridging and increasing the moisture durability of the built assembly. Vapor-permeable exterior insulation, such as mineral board or expanded polystyrene foam, are one such product that may be used to achieve these benefits. However, uncertainty exists on the effects of inward driven moisture and the interaction of increased sheathing temperatures on the moisture durability of the edifice. To address these concerns, Building Science Corporation (BSC) conducted a series of hygrothermal models for cities representing a range of different climate zones. This report describes the research project, key research questions, and the procedures utilized to analyse the problems.

  11. Moisture Durability with Vapor-Permeable Insulating Sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Lepage, R. [Building Science Corporation, Somerville, MA (United States); Lstiburek, J. [Building Science Corporation, Somerville, MA (United States)

    2013-09-01

    Exterior sheathing insulation is an effective strategy in increasing the overall R-value of wall assemblies; other benefits include decreasing the effects of thermal bridging and increasing the moisture durability of the built assembly. Vapor-permeable exterior insulation, such as mineral board or expanded polystyrene foam, are one such product that may be used to achieve these benefits. However,uncertainty exists on the effects of inward driven moisture and the interaction of increased sheathing temperatures on the moisture durability of the edifice. To address these concerns, Building Science Corporation (BSC) conducted a series of hygrothermal models for cities representing a range of different climate zones. This report describes the research project, key research questions, and theprocedures utilized to analyse the problems.

  12. Evaluation of Moisture Buffer Effects by Performing Whole-Building Simulations

    DEFF Research Database (Denmark)

    Rode, Carsten; Mendes, Nathan; K., Grau

    2004-01-01

    The humidity of rooms and the moisture conditions of materials in the enclosure of buildings depend much on each other because of the moisture exchange that takes place over the interior surfaces. These moisture influences also depend strongly on the thermal conditions of indoor spaces...... and enclosure elements of buildings. In turn, the moisture and humidity conditions have significant impact on how buildings are operated. In hot, humid climates, it may be desirable to keep the ventilation rates low in order to avoid too high indoor humidity, while in cold climates, ventilation can be used...

  13. Galvanic Cell Type Sensor for Soil Moisture Analysis.

    Science.gov (United States)

    Gaikwad, Pramod; Devendrachari, Mruthyunjayachari Chattanahalli; Thimmappa, Ravikumar; Paswan, Bhuneshwar; Raja Kottaichamy, Alagar; Makri Nimbegondi Kotresh, Harish; Thotiyl, Musthafa Ottakam

    2015-07-21

    Here we report the first potentiometric sensor for soil moisture analysis by bringing in the concept of Galvanic cells wherein the redox energies of Al and conducting polyaniline are exploited to design a battery type sensor. The sensor consists of only simple architectural components, and as such they are inexpensive and lightweight, making it suitable for on-site analysis. The sensing mechanism is proved to be identical to a battery type discharge reaction wherein polyaniline redox energy changes from the conducting to the nonconducting state with a resulting voltage shift in the presence of soil moisture. Unlike the state of the art soil moisture sensors, a signal derived from the proposed moisture sensor is probe size independent, as it is potentiometric in nature and, hence, can be fabricated in any shape or size and can provide a consistent output signal under the strong aberration conditions often encountered in soil moisture analysis. The sensor is regenerable by treating with 1 M HCl and can be used for multiple analysis with little read out hysteresis. Further, a portable sensor is fabricated which can provide warning signals to the end user when the moisture levels in the soil go below critically low levels, thereby functioning as a smart device. As the sensor is inexpensive, portable, and potentiometric, it opens up avenues for developing effective and energy efficient irrigation strategies, understanding the heat and water transfer at the atmosphere-land interface, understanding soil mechanics, forecasting the risk of natural calamities, and so on.

  14. Isotopic composition of atmospheric moisture from pan water evaporation measurements.

    Science.gov (United States)

    Devi, Pooja; Jain, Ashok Kumar; Rao, M Someshwer; Kumar, Bhishm

    2015-01-01

    A continuous and reliable time series data of the stable isotopic composition of atmospheric moisture is an important requirement for the wider applicability of isotope mass balance methods in atmospheric and water balance studies. This requires routine sampling of atmospheric moisture by an appropriate technique and analysis of moisture for its isotopic composition. We have, therefore, used a much simpler method based on an isotope mass balance approach to derive the isotopic composition of atmospheric moisture using a class-A drying evaporation pan. We have carried out the study by collecting water samples from a class-A drying evaporation pan and also by collecting atmospheric moisture using the cryogenic trap method at the National Institute of Hydrology, Roorkee, India, during a pre-monsoon period. We compared the isotopic composition of atmospheric moisture obtained by using the class-A drying evaporation pan method with the cryogenic trap method. The results obtained from the evaporation pan water compare well with the cryogenic based method. Thus, the study establishes a cost-effective means of maintaining time series data of the isotopic composition of atmospheric moisture at meteorological observatories. The conclusions drawn in the present study are based on experiments conducted at Roorkee, India, and may be examined at other regions for its general applicability.

  15. 19 CFR 151.23 - Allowance for moisture in raw sugar.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Allowance for moisture in raw sugar. 151.23...; DEPARTMENT OF THE TREASURY (CONTINUED) EXAMINATION, SAMPLING, AND TESTING OF MERCHANDISE Sugars, Sirups, and Molasses § 151.23 Allowance for moisture in raw sugar. Inasmuch as the absorption of sea water or moisture...

  16. Experimental study of dynamic effects in moisture transfer in building materials

    DEFF Research Database (Denmark)

    Janssen, Hans; Scheffler, Gregor Albrecht; Plagge, Rudolf

    2016-01-01

    transfer in building materials, similar to moisture transfer in soils, is not free of dynamic effects. The findings imply that the widely accepted static theory for moisture storage in porous media is not generally valid and should be corrected for the occurrences of dynamic effects. Considering......In relation to moisture storage in porous materials, it is often assumed that the process dynamics do not affect the moisture retention. There is mounting evidence though that this notion is incorrect: various studies demonstrate that the moisture retention is influenced by the (de)saturation rates...... of the moisture transfer processes involved. The available evidence primarily stems from imbibition and drainage experiments on soils however, and compared to many other porous media, these tests consider rather permeable materials with relatively dominant liquid transport at comparatively large (de...

  17. An investigation of the moisture sorption and permeability properties of mill-fabricated oriented strandboard

    Science.gov (United States)

    Timusk, Paul Christopher

    This thesis brings the disciplines of Building Science and Wood Science together in the study of the moisture-related properties of oriented strand board (OSB). Using controlled mill-manufactured panels specifically made for this project, this research reveals how the sorption and permeance properties of OSB are affected by several variables including production parameters and physical panel properties, moisture-history, and relative humidity exposure. Since OSB varies in composition through its thickness, this study isolated and tested various core and surface components. Permeability and sorption properties of individual OSB layers, intact panel sections, and panel sections that had undergone cyclic wetting and drying or relative humidity cycling prior to testing, were evaluated. After laboratory testing and analysis, a set of OSB permeance and sorption values were entered into the material database of a finite-element hygrothermal computer modeling program. Relying on this data, a series of hygrothermal wall simulations were carried out using standard wall sections exposed to various climate conditions found throughout North America. These simulations revealed that the results vary widely depending upon the permeance and sorption values used. Thus the common practice of characterizing a range of OSB products with various moisture histories by using a single permeance or sorption value may not be wise.

  18. Use of soil moisture sensors for irrigation scheduling

    Science.gov (United States)

    Various types of soil moisture sensing devices have been developed and are commercially available for water management applications. Each type of soil moisture sensors has its advantages and shortcomings in terms of accuracy, reliability, and cost. Resistive and capacitive based sensors, and time-d...

  19. Moisture corrections in neutron coincidence counting of PuO2

    International Nuclear Information System (INIS)

    Stewart, J.E.; Menlove, H.O.

    1987-01-01

    Passive neutron coincidence counting is capable of 1% assay accuracy for pure, well-characterized PuO 2 samples that contain plutonium masses from a few tens of grams to several kilograms. Moisture in the sample can significantly bias the assay high by changing the (α,n) neutron production, the sample multiplication, and the detection efficiency. Monte Carlo calculations and an analytical model of coincidence counting have been used to quantify the individual and cumulative effects of moisture biases for two PuO 2 sample sizes and a range of moisture levels from 0 to 9 wt %. Results of the calculations suggest a simple correction procedure for moisture bias that is effective from 0 to 3 wt % H 2 O. The procedure requires that the moisture level in the sample be known before the coincidence measurement

  20. Trace moisture emissions from heated metal surfaces in hydrogen service

    International Nuclear Information System (INIS)

    Funke, Hans H.; Yao Jianlong; Raynor, Mark W.

    2004-01-01

    The formation of trace moisture by exposure of dry heated surfaces of 316 L stainless-steel, Restek Silcosteel registered , and nickel 1/8 in. outer diameter line segments to purified Ar and H 2 was studied using atmospheric pressure ionization mass spectrometry at flow rates of 2 slpm. Prior to H 2 exposure, adsorbed moisture was removed by heating incrementally to 500 deg. C in an argon matrix, where the Restek Silcosteel registered material released a maximum of 50 ppb moisture at 300 deg. C and moisture spikes from the Ni and stainless-steel surfaces reached several 100 ppb. Upon exposure to H 2 , persistent low ppb moisture emissions due to the reduction of surface oxide species were observed at temperatures as low as 100 deg. C. Spikes at 300-500 deg. C ranged from ∼100 ppb for the stainless-steel lines to 400 ppb for the Restek Silcosteel registered material. The observed moisture emissions have to be considered as a potential contamination source for high-purity processes utilizing H 2 purge at elevated temperatures

  1. Water activity reduction of intermediate moisture yellowstrip trevally (Selaroides leptolepis

    Directory of Open Access Journals (Sweden)

    Phomajun, P.

    2005-05-01

    Full Text Available Water activity reduction of intermediate moisture yellowstrip trevally was studied. The optimal time (8, 12, 16, 20 hrs. for curing marinade was investigated. The effects of different humectants (glycerol, sorbitol, lactitol, glucose syrup at 50% w/w of curing ingredients were compared. Results showed that moisture content and water activity of cured yellowstrip trevally decreased as curing time increased (p0.05. However, the hardness of intermediate moisture Yellowstrip trevally, determined by texture analyzer, decreased. Hardness, shear force, L a b value of sample added with various humectants were lower than those of the control (p0.05. The glycerol-added samples had the highest overall acceptability score and were higher than control, whereas the glucose syrup-added samples had the lowest score. Moisture content of the samples with the addition of various humectants was higher than that of the control (18.28 %. The samples added with glycerol retained the highest moisture (24.94%. The adsorption isotherm studies showed that the equilibrium moisture of sample added with glycerol was higher than that added with lactitol.

  2. Physically plausible prescription of land surface model soil moisture

    Science.gov (United States)

    Hauser, Mathias; Orth, René; Thiery, Wim; Seneviratne, Sonia

    2016-04-01

    Land surface hydrology is an important control of surface weather and climate, especially under extreme dry or wet conditions where it can amplify heat waves or floods, respectively. Prescribing soil moisture in land surface models is a valuable technique to investigate this link between hydrology and climate. It has been used for example to assess the influence of soil moisture on temperature variability, mean and extremes (Seneviratne et al. 2006, 2013, Lorenz et al., 2015). However, perturbing the soil moisture content artificially can lead to a violation of the energy and water balances. Here we present a new method for prescribing soil moisture which ensures water and energy balance closure by using only water from runoff and a reservoir term. If water is available, the method prevents soil moisture decrease below climatological values. Results from simulations with the Community Land Model (CLM) indicate that our new method allows to avoid soil moisture deficits in many regions of the world. We show the influence of the irrigation-supported soil moisture content on mean and extreme temperatures and contrast our findings with that of earlier studies. Additionally, we will assess how long into the 21st century the new method will be able to maintain present-day climatological soil moisture levels for different regions. Lorenz, R., Argüeso, D., Donat, M.G., Pitman, A.J., den Hurk, B.V., Berg, A., Lawrence, D.M., Chéruy, F., Ducharne, A., Hagemann, S. and Meier, A., 2015. Influence of land-atmosphere feedbacks on temperature and precipitation extremes in the GLACE-CMIP5 ensemble. Journal of Geophysical Research: Atmospheres. Seneviratne, S.I., Lüthi, D., Litschi, M. and Schär, C., 2006. Land-atmosphere coupling and climate change in Europe. Nature, 443(7108), pp.205-209. Seneviratne, S.I., Wilhelm, M., Stanelle, T., Hurk, B., Hagemann, S., Berg, A., Cheruy, F., Higgins, M.E., Meier, A., Brovkin, V. and Claussen, M., 2013. Impact of soil moisture

  3. Comparing soil moisture memory in satellite observations and models

    Science.gov (United States)

    Stacke, Tobias; Hagemann, Stefan; Loew, Alexander

    2013-04-01

    A major obstacle to a correct parametrization of soil processes in large scale global land surface models is the lack of long term soil moisture observations for large parts of the globe. Currently, a compilation of soil moisture data derived from a range of satellites is released by the ESA Climate Change Initiative (ECV_SM). Comprising the period from 1978 until 2010, it provides the opportunity to compute climatological relevant statistics on a quasi-global scale and to compare these to the output of climate models. Our study is focused on the investigation of soil moisture memory in satellite observations and models. As a proxy for memory we compute the autocorrelation length (ACL) of the available satellite data and the uppermost soil layer of the models. Additional to the ECV_SM data, AMSR-E soil moisture is used as observational estimate. Simulated soil moisture fields are taken from ERA-Interim reanalysis and generated with the land surface model JSBACH, which was driven with quasi-observational meteorological forcing data. The satellite data show ACLs between one week and one month for the greater part of the land surface while the models simulate a longer memory of up to two months. Some pattern are similar in models and observations, e.g. a longer memory in the Sahel Zone and the Arabian Peninsula, but the models are not able to reproduce regions with a very short ACL of just a few days. If the long term seasonality is subtracted from the data the memory is strongly shortened, indicating the importance of seasonal variations for the memory in most regions. Furthermore, we analyze the change of soil moisture memory in the different soil layers of the models to investigate to which extent the surface soil moisture includes information about the whole soil column. A first analysis reveals that the ACL is increasing for deeper layers. However, its increase is stronger in the soil moisture anomaly than in its absolute values and the first even exceeds the

  4. Length and time scales of atmospheric moisture recycling

    NARCIS (Netherlands)

    Van der Ent, R.J.; Savenije, H.H.G.

    2011-01-01

    It is difficult to quantify the degree to which terrestrial evaporation supports the occurrence of precipitation within a certain study region (i.e. regional moisture recycling) due to the scale- and shape-dependence of regional moisture recycling ratios. In this paper we present a novel approach to

  5. 7 CFR 801.6 - Tolerances for moisture meters.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Tolerances for moisture meters. 801.6 Section 801.6 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD... FOR GRAIN INSPECTION EQUIPMENT § 801.6 Tolerances for moisture meters. (a) The maintenance tolerances...

  6. Quasi-geostrophic dynamics in the presence of moisture gradients

    OpenAIRE

    Monteiro, Joy M.; Sukhatme, Jai

    2016-01-01

    The derivation of a quasi-geostrophic (QG) system from the rotating shallow water equations on a midlatitude beta-plane coupled with moisture is presented. Condensation is prescribed to occur whenever the moisture at a point exceeds a prescribed saturation value. It is seen that a slow condensation time scale is required to obtain a consistent set of equations at leading order. Further, since the advecting wind fields are geostrophic, changes in moisture (and hence, precipitation) occur only ...

  7. Tracing changes in atmospheric moisture supply to the drying Southwest China

    Directory of Open Access Journals (Sweden)

    C. Zhang

    2017-09-01

    Full Text Available Precipitation over Southwest China (SWC significantly decreased during 1979–2013. The months from July to September (JAS contributed the most to the decrease in precipitation. By tracing moisture sources of JAS precipitation over the SWC region, it is found that most moisture originates in regions from the northern Indian Ocean to SWC and from South China Sea to SWC. The major moisture contributing area is divided into an extended west region, SWC, and an extended east region. The extended west region is mainly influenced by the South Asian summer monsoon (SASM and the westerlies, while the extended east region is mainly influenced by the East Asian summer monsoon (EASM. The extended west, SWC, and extended east regions contribute 48.2, 15.5, and 24.5 % of the moisture for the SWC precipitation, respectively. Moisture supply from the extended west region decreased at a rate of −7.9 mm month−1 decade−1, whereas that from the extended east increased at a rate of 1.4 mm month−1 decade−1, resulting in an overall decrease in moisture supply. Further analysis reveals that the decline of JAS precipitation is mainly caused by change in the seasonal-mean component rather than the transient component of the moisture transport over the SWC region. In addition, the dynamic processes (i.e., changes in wind rather than the thermodynamic processes (i.e., changes in specific humidity are dominant in affecting the seasonal-mean moisture transport. A prevailing easterly anomaly of moisture transport that weakened moisture supply from the Indian Ocean is to a large extent responsible for the precipitation decrease over the SWC region.

  8. Moisture dependence of positron lifetime in Kevlar-49

    Science.gov (United States)

    Singh, Jag J.; Holt, William H.; Mock, Willis, Jr.

    1984-01-01

    Because of filamentary character of Kevlar-49 aramid fibers, there is some concern about the moisture uptake and its effect on plastic composites reinforced with Kevlar-49 fibers. As part of continuing studies of positron lifetime in polymers, we have measured positron lifetime spectra in Kevlar-49 fibers as a function of their moisture content. The long lifetime component intensities are rather low, being only of the order of 2-3 percent. The measured values of long component lifetimes at various moisture levels in the specimens are as follows: 2072 +/- 173 ps (dry); 2013 +/- 193 ps (20.7 percent saturation); 1665 +/- 85 ps (25.7 percent saturation); 1745 +/- 257 ps (32.1 percent saturation); and 1772 +/- 217 ps (100 percent saturation). It is apparent that the long component lifetime at first decreases and then increases as the specimen moisture content increases. These results have been compared with those inferred from Epon-815 and Epon-815/K-49 composite data.

  9. Increase of Steam Moisture in the BWR-Facility KKP 1

    International Nuclear Information System (INIS)

    Noack, Volker

    2002-01-01

    Main steam moisture in a BWR facility is determined by steam quality at core outlet and efficiency of steam separators and steam dryers. Transport of water with steam is accompanied by transport of radionuclides out of RPV resulting in enhanced radiation level in the main steam system. A remarkable increase of main steam moisture started at KKP 1 in 1997. In the following years increase of steam outlet moisture started at lower and lower core mass flow rates. Dose rate in main steam system increased simultaneously. Core mass flow rate and thus thermal power had to be reduced during stretch out operation to keep the main steam moisture below the specified boundary of 0.2 %. This boundary also guarantees, that radiological exposure remains far below approved values. The increase of main steam moisture corresponds with the application of low leakage core loading. Low leakage core loading results in enhanced steam generation in the center and in reduced steam generation in the outer zones of the core. It can be shown, that the uneven steam generation in the core became stronger over the years. Therefore, steam quality at inlet of the outer steam separators was getting lower. This resulted in higher carry over of water in this steam separators and steam dryers, thus explaining the increasing main steam moisture. KKP 1 started in 2000 with spectral shift operation. As one should expect, this resulted in reduced steam moisture. It remains the question of steam moisture in case of stretch out operation. Countermeasures are briefly discussed. (authors)

  10. Variação do teor de umidade e da densidade básica na madeira de sete espécies de eucalipto Variation of the moisture content and specific gravity in the wood of seven eucalypt species

    Directory of Open Access Journals (Sweden)

    José Tarcísio da Silva Oliveira

    2005-02-01

    Full Text Available As variações de umidade e da densidade do lenho das árvores são as principais causas dos defeitos de secagem, como o empenamento e fendilhamento das peças de madeira. Os tipos de madeira presentes em um tronco estão relacionados com as variações dessas duas importantes propriedades físicas. Os gradientes de umidade e da densidade da madeira de sete espécies de eucalipto foram avaliados nas direções radial e longitudinal do tronco de árvores recém-abatidas. Os resultados apontaram uma maior homogeneidade de distribuição de umidade dentro das árvores de E. paniculata e E. citriodora, indicada pelos coeficientes de variação e desvio-padrão. O diferencial de umidade da madeira nas regiões internas do tronco de E. paniculata e E. citriodora foi de 20% e de E. urophylla e E. grandis, de 80%. A densidade básica da madeira aumentou na direção radial do tronco, e cada espécie de eucalipto apresentou um modelo de variação.The occurrence of high moisture and density gradients inside of the tree is related with drying defects, especially those characterized by warp and split of the wood. The unequal behavior of wood pieces due to variation of these two properties can be attributed to differences within the wood that constitutes the log. Considering the importance of knowing the moisture and density gradients in eucalyptus trees, this work had as objective evaluating the variations of the moisture content and specific gravity in the radial and longitudinal directions of the trees of seven eucalypts species. Based on the results concerning the moisture distribution inside the tree, there was a great homogeneity in the species of E. paniculata and E. citriodora, sustained by the low values of variation coefficient and standard deviation. In these species, the moisture differential among the inner and outer parts of the log rarely reached 20%, while for the logs of E. urophylla and E. grandis, this diferencial reached 80%. In spite of

  11. Combined Radar-Radiometer Surface Soil Moisture and Roughness Estimation

    Science.gov (United States)

    Akbar, Ruzbeh; Cosh, Michael H.; O'Neill, Peggy E.; Entekhabi, Dara; Moghaddam, Mahta

    2017-01-01

    A robust physics-based combined radar-radiometer, or Active-Passive, surface soil moisture and roughness estimation methodology is presented. Soil moisture and roughness retrieval is performed via optimization, i.e., minimization, of a joint objective function which constrains similar resolution radar and radiometer observations simultaneously. A data-driven and noise-dependent regularization term has also been developed to automatically regularize and balance corresponding radar and radiometer contributions to achieve optimal soil moisture retrievals. It is shown that in order to compensate for measurement and observation noise, as well as forward model inaccuracies, in combined radar-radiometer estimation surface roughness can be considered a free parameter. Extensive Monte-Carlo numerical simulations and assessment using field data have been performed to both evaluate the algorithms performance and to demonstrate soil moisture estimation. Unbiased root mean squared errors (RMSE) range from 0.18 to 0.03 cm3cm3 for two different land cover types of corn and soybean. In summary, in the context of soil moisture retrieval, the importance of consistent forward emission and scattering development is discussed and presented.

  12. A neutron moisture system on nickel mineral transport rubber belt

    International Nuclear Information System (INIS)

    Jia Wenbao; Su Tongling; Zhang Xiaomin

    2000-01-01

    A method of density-thickness joint compensation was developed to make the on-line measurement of moisture for moving irregular mineral materials. At the same time, the materials' thickness, as a weighted factor, was chosen to modify the prompt moisture in a fixed time and improve the accuracy of measuring moisture. The experimental data show that the measurement accuracy is better than 5% for a thickness of > 2 cm and a moisture of > 6%. The system has been running on the spot for about three months, with a result accorded with that by the stoving-weighing method

  13. Time series modeling of soil moisture dynamics on a steep mountainous hillside

    Science.gov (United States)

    Kim, Sanghyun

    2016-05-01

    The response of soil moisture to rainfall events along hillslope transects is an important hydrologic process and a critical component of interactions between soil vegetation and the atmosphere. In this context, the research described in this article addresses the spatial distribution of soil moisture as a function of topography. In order to characterize the temporal variation in soil moisture on a steep mountainous hillside, a transfer function, including a model for noise, was introduced. Soil moisture time series with similar rainfall amounts, but different wetness gradients were measured in the spring and fall. Water flux near the soil moisture sensors was modeled and mathematical expressions were developed to provide a basis for input-output modeling of rainfall and soil moisture using hydrological processes such as infiltration, exfiltration and downslope lateral flow. The characteristics of soil moisture response can be expressed in terms of model structure. A seasonal comparison of models reveals differences in soil moisture response to rainfall, possibly associated with eco-hydrological process and evapotranspiration. Modeling results along the hillslope indicate that the spatial structure of the soil moisture response patterns mainly appears in deeper layers. Similarities between topographic attributes and stochastic model structures are spatially organized. The impact of temporal and spatial discretization scales on parameter expression is addressed in the context of modeling results that link rainfall events and soil moisture.

  14. Influence of Inherent Moisture Content on the Deformation ...

    African Journals Online (AJOL)

    Influence of Inherent Moisture Content on the Deformation. Properties of Coconut Tissues During Mechanical Oil. Expression. *J. J. Mpagalile1 and B. Clarke2. 1Department of ... The study confirmed that moisture content has an important role in the deformation of coconut ..... A micro penetration technique for mechanical.

  15. Estimating Regional Scale Hydroclimatic Risk Conditions from the Soil Moisture Active-Passive (SMAP Satellite

    Directory of Open Access Journals (Sweden)

    Catherine Champagne

    2018-04-01

    Full Text Available Satellite soil moisture is a critical variable for identifying susceptibility to hydroclimatic risks such as drought, dryness, and excess moisture. Satellite soil moisture data from the Soil Moisture Active/Passive (SMAP mission was used to evaluate the sensitivity to hydroclimatic risk events in Canada. The SMAP soil moisture data sets in general capture relative moisture trends with the best estimates from the passive-only derived soil moisture and little difference between the data at different spatial resolutions. In general, SMAP data sets overestimated the magnitude of moisture at the wet extremes of wetting events. A soil moisture difference from average (SMDA was calculated from SMAP and historical Soil Moisture and Ocean Salinity (SMOS data showed a relatively good delineation of hydroclimatic risk events, although caution must be taken due to the large variability in the data within risk categories. Satellite soil moisture data sets are more sensitive to short term water shortages than longer term water deficits. This was not improved by adding “memory” to satellite soil moisture indices to improve the sensitivity of the data to drought, and there is a large variability in satellite soil moisture values with the same drought severity rating.

  16. Effect of moisture content on strength of CCA-treated lumber

    Science.gov (United States)

    Jerrold E. Winandy

    1995-01-01

    Recent studies on the effects of chromated copper arsenate (CCA) treatment on lumber design properties have primarily evaluated the effects of such treatment at or near 12% moisture content and at failure times of 1 to 10 min. The influence of various moisture contents and faster loading rates is unknown. This report discusses the influence of moisture content and its...

  17. Effects of moisture content on some physical properties of red ...

    African Journals Online (AJOL)

    The physical properties of red pepper seed were evaluated as a function of moisture content. The average length, width and thickness were 4.46, 3.66 and 0.79 mm, respectively, at 7.27% d.b. moisture content. In the moisture range of 7.27 to 20.69% dry basis (d.b.), studies on rewetted red pepper seed showed that the ...

  18. McMaster Mesonet soil moisture dataset: description and spatio-temporal variability analysis

    Directory of Open Access Journals (Sweden)

    K. C. Kornelsen

    2013-04-01

    Full Text Available This paper introduces and describes the hourly, high-resolution soil moisture dataset continuously recorded by the McMaster Mesonet located in the Hamilton-Halton Watershed in Southern Ontario, Canada. The McMaster Mesonet consists of a network of time domain reflectometer (TDR probes collecting hourly soil moisture data at six depths between 10 cm and 100 cm at nine locations per site, spread across four sites in the 1250 km2 watershed. The sites for the soil moisture arrays are designed to further improve understanding of soil moisture dynamics in a seasonal climate and to capture soil moisture transitions in areas that have different topography, soil and land cover. The McMaster Mesonet soil moisture constitutes a unique database in Canada because of its high spatio-temporal resolution. In order to provide some insight into the dominant processes at the McMaster Mesonet sites, a spatio-temporal and temporal stability analysis were conducted to identify spatio-temporal patterns in the data and to suggest some physical interpretation of soil moisture variability. It was found that the seasonal climate of the Great Lakes Basin causes a transition in soil moisture patterns at seasonal timescales. During winter and early spring months, and at the meadow sites, soil moisture distribution is governed by topographic redistribution, whereas following efflorescence in the spring and summer, soil moisture spatial distribution at the forested site was also controlled by vegetation canopy. Analysis of short-term temporal stability revealed that the relative difference between sites was maintained unless there was significant rainfall (> 20 mm or wet conditions a priori. Following a disturbance in the spatial soil moisture distribution due to wetting, the relative soil moisture pattern re-emerged in 18 to 24 h. Access to the McMaster Mesonet data can be provided by visiting www.hydrology.mcmaster.ca/mesonet.

  19. The modulation of oceanic moisture transport by the hemispheric annular modes

    Directory of Open Access Journals (Sweden)

    Raquel eNieto

    2014-07-01

    Full Text Available Leaving aside the contribution made by recycling, it is the main oceanic moisture sources that are responsible for most of the precipitation that falls on the continents. The transport of moisture from these sources can be affected by large-scale variability according to the hemispheric annular modes. The influence of the two dominant modes of extratropical winter climate: the Northern and the Southern Annular Modes (NAM and SAM are herein investigated to assess how they affect the transport of moisture from the major oceanic moisture sources. A Lagrangian model was used, together with ERA-Interim reanalysis data (1979-2012, and differences between the composites of the six strongest higher and lower events observed for both phases of the two modes for the period were analysed. The method is able to reproduce the general pattern of known variations for both annular patterns. Lower values of the NAM Index are associated with the displacement of the storm track towards tropical latitudes. Thus, moisture transport is enhanced from the Northern Pacific towards the northeastern basin and from the Northern Atlantic and Mediterranean towards southern Europe. On the other hand, during higher values of NAM, moisture transport is favoured from the Northern Pacific towards eastern Asia, and moisture transport is enhanced from the Northern Atlantic towards the Caribbean Sea. In the Southern Hemisphere, during higher values of SAM more moisture is transported from the Atlantic and Indian oceanic sources southwards and eastwards than during the opposite phase. In this SAM phase it is also noted by an enhancement of moisture transport from the Coral Sea and Southern Pacific sources towards the Indian Ocean/West Pacific Warm Pool. Southeastern South America received more moisture from the Pacific and Atlantic sources during years with a lower SAM, episodes which also favoured the influx of moisture from the Southern Atlantic towards Africa, causing monsoon

  20. Radar for Measuring Soil Moisture Under Vegetation

    Science.gov (United States)

    Moghaddam, Mahta; Moller, Delwyn; Rodriguez, Ernesto; Rahmat-Samii, Yahya

    2004-01-01

    A two-frequency, polarimetric, spaceborne synthetic-aperture radar (SAR) system has been proposed for measuring the moisture content of soil as a function of depth, even in the presence of overlying vegetation. These measurements are needed because data on soil moisture under vegetation canopies are not available now and are necessary for completing mathematical models of global energy and water balance with major implications for global variations in weather and climate.

  1. Factors influencing moisture analysis in the 3013 destructive examination surveillance program

    Energy Technology Data Exchange (ETDEWEB)

    Scogin, J. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-10-24

    Thermogravimetric analysis of a solid sample with mass spectrometry (TGA-MS) of the evolved gas is used in the destructive examination (DE) portion of the Integrated Surveillance Program to quantify the moisture content of the material stored in a 3013 container. As with any measurement determined from a small sample, the collection, storage, transportation, and handling of the sample can affect its ability to represent the properties of the bulk material. During the course of the DE program, questions have periodically arisen concerning the ability of the moisture sample to reflect reliably the actual moisture content of the entire material stored in the 3013 container. Most concerns are related to the ability to collect a representative sample and to preserve the moisture content of the sample between collection and analysis. Recent delays in analysis caused by maintenance issues with the TGA-MS instrument presented a unique opportunity to document and quantify the effects various factors have on the TGA-MS moisture measurement. This report will use recent data to document the effects that current sample collection and handling practices have on the TGA-MS moisture measurement. Some suggestions will be made which could improve the current sample collection and handling practices for the TGA-MS moisture measurement so that the analytical results more accurately reflect the moisture content of the material stored in the 3013 container.

  2. Factors influencing moisture analysis in the 3013 destructive examination surveillance program

    International Nuclear Information System (INIS)

    Scogin, J. H.

    2017-01-01

    Thermogravimetric analysis of a solid sample with mass spectrometry (TGA-MS) of the evolved gas is used in the destructive examination (DE) portion of the Integrated Surveillance Program to quantify the moisture content of the material stored in a 3013 container. As with any measurement determined from a small sample, the collection, storage, transportation, and handling of the sample can affect its ability to represent the properties of the bulk material. During the course of the DE program, questions have periodically arisen concerning the ability of the moisture sample to reflect reliably the actual moisture content of the entire material stored in the 3013 container. Most concerns are related to the ability to collect a representative sample and to preserve the moisture content of the sample between collection and analysis. Recent delays in analysis caused by maintenance issues with the TGA-MS instrument presented a unique opportunity to document and quantify the effects various factors have on the TGA-MS moisture measurement. This report will use recent data to document the effects that current sample collection and handling practices have on the TGA-MS moisture measurement. Some suggestions will be made which could improve the current sample collection and handling practices for the TGA-MS moisture measurement so that the analytical results more accurately reflect the moisture content of the material stored in the 3013 container.

  3. Optimum moisture levels for biodegradation of mortality composting envelope materials.

    Science.gov (United States)

    Ahn, H K; Richard, T L; Glanville, T D

    2008-01-01

    Moisture affects the physical and biological properties of compost and other solid-state fermentation matrices. Aerobic microbial systems experience different respiration rates (oxygen uptake and CO2 evolution) as a function of moisture content and material type. In this study the microbial respiration rates of 12 mortality composting envelope materials were measured by a pressure sensor method at six different moisture levels. A wide range of respiration (1.6-94.2mg O2/g VS-day) rates were observed for different materials, with alfalfa hay, silage, oat straw, and turkey litter having the highest values. These four envelope materials may be particularly suitable for improving internal temperature and pathogen destruction rates for disease-related mortality composting. Optimum moisture content was determined based on measurements across a range that spans the maximum respiration rate. The optimum moisture content of each material was observed near water holding capacity, which ranged from near 60% to over 80% on a wet basis for all materials except a highly stabilized soil compost blend (optimum around 25% w.b.). The implications of the results for moisture management and process control strategies during mortality composting are discussed.

  4. Divergent surface and total soil moisture projections under global warming

    Science.gov (United States)

    Berg, Alexis; Sheffield, Justin; Milly, Paul C.D.

    2017-01-01

    Land aridity has been projected to increase with global warming. Such projections are mostly based on off-line aridity and drought metrics applied to climate model outputs but also are supported by climate-model projections of decreased surface soil moisture. Here we comprehensively analyze soil moisture projections from the Coupled Model Intercomparison Project phase 5, including surface, total, and layer-by-layer soil moisture. We identify a robust vertical gradient of projected mean soil moisture changes, with more negative changes near the surface. Some regions of the northern middle to high latitudes exhibit negative annual surface changes but positive total changes. We interpret this behavior in the context of seasonal changes in the surface water budget. This vertical pattern implies that the extensive drying predicted by off-line drought metrics, while consistent with the projected decline in surface soil moisture, will tend to overestimate (negatively) changes in total soil water availability.

  5. Resistência ao impacto da madeira de nogueira-pecã em diferentes condições de umidade Impact strength of nogueira-pecã wood on different moisture conditions

    Directory of Open Access Journals (Sweden)

    Rafael Beltrame

    2012-09-01

    Full Text Available Os estudos de resistência da madeira ao impacto referem-se à eficiência com que este material absorve energia de um impacto e dissipa-a sem danos a sua estrutura. Dessa forma, o objetivo deste estudo foi avaliar a influência do teor de umidade na resistência ao impacto da madeira de nogueira-pecã (Carya illinoinensis. Para tanto, foram utilizadas árvores procedentes de duas regiões fisiográficas do estado do Rio Grande do Sul. Os corpos de prova, em condições de equilíbrio a 12% de umidade e saturados, foram submetidos ao impacto utilizando-se pêndulo de CHARPY, e avaliados quanto à resistência oferecida com a aplicação da carga nos planos tangencial e radial e posições de retirada (medula - casca nas toras, para as duas regiões fisiográficas em cada condição de umidade. Para auxiliar na interpretação dos dados, determinou-se a massa específica aparente a 12% e saturada, trabalho absorvido, coeficiente de resiliência e a cota dinâmica. Pôde-se verificar, por meio dos resultados, que a madeira de nogueira-pecã é mais resistente ao impacto na condição saturada.The studies of wood impact strength refers to the efficiency of this material in absorb impact energy and dissipate it without structural damages. The present study aimed to evaluate the influence of moisture content on the impact strength of nogueira-pecã (Carya illinoinensis wood. For this, trees from two physiographic regions of state of Rio Grande do Sul were used. The samples, stabilized at 12% of moisture content and in green conditions (saturated, were submitted to impact tests through a CHARPY pendulum, and were evaluated for the resistance to the application of loads in the tangential and radial sections, and in the positions of the log (pith-bark for the two physiographic regions at each moisture condition. Moreover, the apparent specific gravity at 12% and in green conditions (saturated, the absorbed work, the resilience coefficient and the

  6. Determination of moisture in bagasse by neutron reflection

    International Nuclear Information System (INIS)

    Diaz Rizo, O.; Suarez, J.C.

    1990-01-01

    For the first time in Cuba organic samples were analyzed by neutron reflection method. The feasibility of this method to determinate the moisture grade in sugar cane bagasse is fixed. From 0 to 50w% moisture grade with 2-3% relative accuracy can be determinated using 10m. measuring time. 7 refs

  7. Soil moisture estimation using reflected solar and emitted thermal infrared radiation

    Science.gov (United States)

    Jackson, R. D.; Cihlar, J.; Estes, J. E.; Heilman, J. L.; Kahle, A.; Kanemasu, E. T.; Millard, J.; Price, J. C.; Wiegand, C. L.

    1978-01-01

    Classical methods of measuring soil moisture such as gravimetric sampling and the use of neutron moisture probes are useful for cases where a point measurement is sufficient to approximate the water content of a small surrounding area. However, there is an increasing need for rapid and repetitive estimations of soil moisture over large areas. Remote sensing techniques potentially have the capability of meeting this need. The use of reflected-solar and emitted thermal-infrared radiation, measured remotely, to estimate soil moisture is examined.

  8. Moisture buffer capacity of different insulation materials

    DEFF Research Database (Denmark)

    Peuhkuri, Ruut Hannele; Rode, Carsten; Hansen, Kurt Kielsgaard

    2004-01-01

    . In the isothermal tests the material samples were exposed to the same change in the relative humidity of the ambient air on both sides, while the samples were exposed to variations in relative humidity only on the cold side in the non-isothermal tests. The results of these rather different measurement principles...... lead to more durable constructions. In this paper, a large range of very different thermal insulation materials have been tested in specially constructed laboratory facilities to determine their moisture buffer capacity. Both isothermal and nonisothermal experimental set-ups have been used...... are discussed, and different ways are presented how to determine the moisture buffer capacity of the materials using partly standard material parameters and partly parameters determined from the actual measurements. The results so far show that the determination of moisture buffer capacity is very sensitive...

  9. Moisture Forecast Bias Correction in GEOS DAS

    Science.gov (United States)

    Dee, D.

    1999-01-01

    Data assimilation methods rely on numerous assumptions about the errors involved in measuring and forecasting atmospheric fields. One of the more disturbing of these is that short-term model forecasts are assumed to be unbiased. In case of atmospheric moisture, for example, observational evidence shows that the systematic component of errors in forecasts and analyses is often of the same order of magnitude as the random component. we have implemented a sequential algorithm for estimating forecast moisture bias from rawinsonde data in the Goddard Earth Observing System Data Assimilation System (GEOS DAS). The algorithm is designed to remove the systematic component of analysis errors and can be easily incorporated in an existing statistical data assimilation system. We will present results of initial experiments that show a significant reduction of bias in the GEOS DAS moisture analyses.

  10. Moisture Distribution in Broccoli: Measurements by MRI Hot Air Drying Experiments

    NARCIS (Netherlands)

    Jin, X.; Sman, van der R.G.M.; Gerkema, E.; Vergeldt, F.J.; As, van H.; Boxtel, van A.J.B.

    2011-01-01

    ABSTRACT The internal moisture distribution that arise in food products during drying, is a key factor for the retention of quality attributes. To reveal the course of moisture content in a product, internal moisture profiles in broccoli florets are measured by MRI imaging during drying experiments

  11. Moisture distribution in broccoli: measurements by MRI hot air drying experiments

    NARCIS (Netherlands)

    Jin, X.; Sman, van der R.G.M.; Gerkema, E.; Vergeldt, F.J.; As, van H.; Boxtel, van A.J.B.

    2011-01-01

    The internal moisture distribution that arise in food products during drying, is a key factor for the retention of quality attributes. To reveal the course of moisture content in a product, internal moisture profiles in broccoli florets are measured by MRI imaging during drying experiments with

  12. Extent of moisture and mould damage in structures of public buildings

    Directory of Open Access Journals (Sweden)

    Petri J. Annila

    2017-06-01

    Full Text Available The study concentrated on the extent of moisture and mould damage in different structures in 25 public buildings in Finland. Users of all the buildings had health symptoms suspected to be the result of moisture and mould damage, which is why moisture performance assessments had been performed. The assessment reports on each building were available as research material. The reports indicated that the examined buildings suffered from multiple moisture and mould problems in several different structures. On average, however, a relatively small proportion of the total number of structures had suffered damage. On the basis of the research material, damage was most extensive in walls in soil contact (16.3% and base floor structures (12.5%. The lowest damage rates were found in partition walls (2.4%, external walls (2.6% and intermediate floors (2.5%. The results of the study underline the importance of thorough moisture performance assessments to ensure that all point-sized moisture and mould damage is detected.

  13. Review: Moisture loading—the hidden information in groundwater observation well records

    Science.gov (United States)

    van der Kamp, Garth; Schmidt, Randy

    2017-12-01

    Changes of total moisture mass above an aquifer such as snow accumulation, soil moisture, and storage at the water table, represent changes of mechanical load acting on the aquifer. The resulting moisture-loading effects occur in all observation well records for confined aquifers. Deep observation wells therefore act as large-scale geological weighing lysimeters, referred to as "geolysimeters". Barometric pressure effects on groundwater levels are a similar response to surface loading and are familiar to every hydrogeologist dealing with the "barometric efficiency" of observation wells. Moisture-loading effects are small and generally not recognized because they are obscured by hydraulic head fluctuations due to other causes, primarily barometric pressure changes. For semiconfined aquifers, long-term moisture-loading effects may be dissipated and obscured by transient flow through overlying aquitards. Removal of barometric and earth tide effects from observation well records allows identification of moisture loading and comparison with hydrological observations, and also comparison with the results of numerical models that can account for transient groundwater flow.

  14. Evaporational losses under different soil moisture regimes and atmospheric evaporativities using tritium

    International Nuclear Information System (INIS)

    Saxena, P.; Chaudhary, T.N.; Mookerji, P.

    1991-01-01

    Tritium as tracer was used in a laboratory study to estimate the contribution of moisture from different soil depths towards actual soil water evaporation. Results indicated that for comparable amounts of free water evaporation (5 cm), contribution of moisture from 70-80 cm soil layer towards total soil moisture loss through evaporation increased nearly 1.5 to 3 folds for soils with water table at 90 cm than without water table. Identical initial soil moistures were exposed to different atmospheric evaporativities. Similarly, for a given initial soil moisture status, upward movement of moisture from 70-80 cm soil layer under low evaporativity was nearly 8 to 12 times that of under high evaporativity at 5 cm free water evaporation value. (author). 6 refs., 4 tabs., 2 figs

  15. SMOS/SMAP Synergy for SMAP Level 2 Soil Moisture Algorithm Evaluation

    Science.gov (United States)

    Bindlish, Rajat; Jackson, Thomas J.; Zhao, Tianjie; Cosh, Michael; Chan, Steven; O'Neill, Peggy; Njoku, Eni; Colliander, Andreas; Kerr, Yann

    2011-01-01

    Soil Moisture Active Passive (SMAP) satellite has been proposed to provide global measurements of soil moisture and land freeze/thaw state at 10 km and 3 km resolutions, respectively. SMAP would also provide a radiometer-only soil moisture product at 40-km spatial resolution. This product and the supporting brightness temperature observations are common to both SMAP and European Space Agency's Soil Moisture and Ocean Salinity (SMOS) mission. As a result, there are opportunities for synergies between the two missions. These include exploiting the data for calibration and validation and establishing longer term L-band brightness temperature and derived soil moisture products. In this investigation we will be using SMOS brightness temperature, ancillary data, and soil moisture products to develop and evaluate a candidate SMAP L2 passive soil moisture retrieval algorithm. This work will begin with evaluations based on the SMOS product grids and ancillary data sets and transition to those that will be used by SMAP. An important step in this analysis is reprocessing the multiple incidence angle observations provided by SMOS to a global brightness temperature product that simulates the constant 40 degree incidence angle observations that SMAP will provide. The reprocessed brightness temperature data provide a basis for evaluating different SMAP algorithm alternatives. Several algorithms are being considered for the SMAP radiometer-only soil moisture retrieval. In this first phase, we utilized only the Single Channel Algorithm (SCA), which is based on the radiative transfer equation and uses the channel that is most sensitive to soil moisture (H-pol). Brightness temperature is corrected sequentially for the effects of temperature, vegetation, roughness (dynamic ancillary data sets) and soil texture (static ancillary data set). European Centre for Medium-Range Weather Forecasts (ECMWF) estimates of soil temperature for the top layer (as provided as part of the SMOS

  16. Calibration technique for the neutron surface moisture measurement system

    International Nuclear Information System (INIS)

    Watson, W.T.; Shreve, D.C.

    1996-01-01

    A technique for calibrating the response of a surface neutron moisture measurement probe to material moisture concentration has been devised. Tests to ensure that the probe will function in the expected in-tank operating environment are also outlined

  17. Experience of Implementing Moisture Sorption Control in Historical Archives

    Directory of Open Access Journals (Sweden)

    P. Zítek

    2006-01-01

    Full Text Available This paper deals with a novel approach to inhibiting the harmful impact of moisture sorption in old art works and historical exhibits preserved in remote historic buildings that are in use as depositories or exhibition rooms for cultural heritage collections. It is a sequel to the previous work presented in [2], where the principle of moisture sorption stabilization was explained. Sorption isotherm investigations and EMC control implementation in historical buildings not provided with heating are the main concern in this paper. The proposed microclimate adjustment consists in leaving the interior temperature to run almost its spontaneous yearly cycle, while the air humidity is maintained in a specific relationship to the current interior temperature. The interior air humidity is modestly adjusted to protect historical exhibits and art works from harmful variations in the content of absorbed moisture, which would otherwise arise owing to the interior temperature drifts. Since direct measurements of moisture content are not feasible, the air humidity is controlled via a model-based principle. Two long-term implementations of the proposed microclimate control have already proved that it can permanently maintain a constant moisture content in the preserved exhibits. 

  18. Soil moisture remote sensing: State of the science

    Science.gov (United States)

    Satellites (e.g., SMAP, SMOS) using passive microwave techniques, in particular at L band frequency, have shown good promise for global mapping of near-surface (0-5 cm) soil moisture at a spatial resolution of 25-40 km and temporal resolution of 2-3 days. C- and X-band soil moisture records date bac...

  19. Reliability-Based Modeling of Moisture and Load-Duration Effects

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Svensson, Staffan

    2005-01-01

    Load duration effects with respect to reduction of load bearing capacity are very important for structural timber. This paper describes how the load duration effects combined with moisture content and variations c an be determined on basis of simulation of realizations of the time varying load...... and moisture processes. Permanent and snow load sand moisture variations are considered and stochastic models are formulated in accordance with the load models in the Danish structural codes. A damage accumulation model based on fracture mechanics that accounts for both load duration and moisture effects...... is derived. The parameters in the model are fitted to data relevant for Nordic structural timber using the Maximum Likelihood method. The probability of failure as function of time is estimated for representative limit states based on: a) short term strength and b) long term damage accumulation...

  20. Effects of Moisture Content on the Foundry Properties of Yola Natural Sand

    Directory of Open Access Journals (Sweden)

    Paul Aondona IHOM

    2012-08-01

    Full Text Available The effect of moisture content of Yola natural sand has been studied. The moisture content was varied from 1 to 9%. The effect of the moisture content on the green compression strength, green permeability and bulk density was investigated. Particle size distribution of the natural sand, the grain fineness number, average grain size, grain shape and the clay content of the natural sand were also studied. 5% moisture gave the optimum green compression strength of 118.6KN/m2. The dry compression strength increased with moisture content, an optimum value of 4000KN/m2 was obtained at 9% moisture. The Yola natural sand had a grain fineness number of 88.05AFS, average grain size of 335.78 microns and a clay content of 26%. A sand mixture containing 5% moisture was prepared and used to produce a test casting with aluminium scraps, the test casting was sound.

  1. Evapotranspiration Estimates for a Stochastic Soil-Moisture Model

    Science.gov (United States)

    Chaleeraktrakoon, Chavalit; Somsakun, Somrit

    2009-03-01

    Potential evapotranspiration is information that is necessary for applying a widely used stochastic model of soil moisture (I. Rodriguez Iturbe, A. Porporato, L. Ridolfi, V. Isham and D. R. Cox, Probabilistic modelling of water balance at a point: The role of climate, soil and vegetation, Proc. Roy. Soc. London A455 (1999) 3789-3805). An objective of the present paper is thus to find a proper estimate of the evapotranspiration for the stochastic model. This estimate is obtained by comparing the calculated soil-moisture distribution resulting from various techniques, such as Thornthwaite, Makkink, Jensen-Haise, FAO Modified Penman, and Blaney-Criddle, with an observed one. The comparison results using five sequences of daily soil-moisture for a dry season from November 2003 to April 2004 (Udornthani Province, Thailand) have indicated that all methods can be used if the weather information required is available. This is because their soil-moisture distributions are alike. In addition, the model is shown to have its ability in approximately describing the phenomenon at a weekly or biweekly time scale which is desirable for agricultural engineering applications.

  2. Specialized moisture retention eyewear for evaporative dry eye.

    Science.gov (United States)

    Waduthantri, Samanthila; Tan, Chien Hua; Fong, Yee Wei; Tong, Louis

    2015-05-01

    To evaluate the suitablity of commercially available moisture retention eyewear for treating evaporative dry eye. Eleven patients with evaporative dry eyes were prescibed moisture retention eyewear for 3 months in addition to regular lubricant eye drops. Frequency and severity of dry eye symptoms, corneal fluorescein staining and tear break up time (TBUT) were evaluated at baseline and 3-month post-treatment. Main outcome measure was global symptom score (based on severity and frequency of dry eye symptoms on a visual analog scale) and secondary outcomes were changes in sectoral corneal fluorescein staining and tear break up time (TBUT) from pre-treatment level. There was a significant improvement in dry eye symptoms after using moisture retention eyewear for 3 months (p eyes improved significantly (p dry eye symptoms in windy, air-conditioned environments or when doing vision-related daily tasks. This study shows that moisture retention eyewear might be a valuable adjunct in management of evaporative dry eye and this new design of commercially available eyewear could have a good acceptability rate.

  3. Estimating soil moisture using the Danish polarimetric SAR

    DEFF Research Database (Denmark)

    Jiankang, Ji; Thomsen, A.; Skriver, Henning

    1995-01-01

    The results of applying data from the Danish polarimetric SAR (EMISAR) to estimate soil moisture for bare fields are presented. Fully calibrated C-band SAR images for hh, vv and cross polarizations have been used in this study. The measured surface roughness data showed that classical roughness a...... of surface parameters with the bilinear model, the correlation coefficient between the estimated and measured soil moisture, as well as rms height, is about 0.77. To improve the result, the local incidence angles need to be taken into account......The results of applying data from the Danish polarimetric SAR (EMISAR) to estimate soil moisture for bare fields are presented. Fully calibrated C-band SAR images for hh, vv and cross polarizations have been used in this study. The measured surface roughness data showed that classical roughness...... autocorrelation functions (Gaussian and Exponential) were not able to fit natural surfaces well. A Gauss-Exp hybrid model which agreed better with the measured data has been proposed. Theoretical surface scattering models (POM, IEM), as well as an empirical model for retrieval of soil moisture and surface rms...

  4. ETEM observation of Pt/C electrode catalysts in a moisturized cathode atmosphere

    International Nuclear Information System (INIS)

    Yoshida, K; Zhang, X; Tanaka, N; Boyes, E D; Gai, P L

    2014-01-01

    There have been reports of challenges in designing platinum carbon (Pt/C) electrode catalysts for PEMFC. Pt/C electrode catalysts deactivate much faster on the cathode (in moisturized O 2 ) than on the anode (in H 2 ). To understand influences of moisture and oxygen on the deactivation of the Pt/C catalysts in proton-exchange-membrane fuel cells (PEMFCs), spherical-aberration-corrected environmental transmission electron microscopy (AC-ETEM) was applied with a high-speed CCD camera. Structural changes of the Pt/C electrode catalysts were dynamically recorded in moisturized nitrogen, oxygen and hydrogen. The mass spectrometry confirmed the moisture content (between 5 to 30 %) of nitrogen driving gas through a humidifier. Coalescence of platinum nanoparticles (D = 3.24 nm) was carefully evaluated in pure N 2 and moisturized N 2 atmosphere. The Pt/C showed considerable structural weakness in a moisturized N2 atmosphere. Comparable results obtained by AC-ETEM in different gas atmospheres also suggested ways to improve the oxygen reduction reaction (ORR). In this paper, the deactivation process due to moisture (hydroxylation) of carbon supports is discussed using for comparison the movement of platinum nanoparticles measured in moisturized nitrogen and pure nitrogen atmospheres

  5. Observer Based Fault Detection and Moisture Estimating in Coal Mill

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Mataji, Babak

    2008-01-01

    In this paper an observer-based method for detecting faults and estimating moisture content in the coal in coal mills is presented. Handling of faults and operation under special conditions, such as high moisture content in the coal, are of growing importance due to the increasing...... requirements to the general performance of power plants. Detection  of faults and moisture content estimation are consequently of high interest in the handling of the problems caused by faults and moisture content. The coal flow out of the mill is the obvious variable to monitor, when detecting non-intended drops in the coal...... flow out of the coal mill. However, this variable is not measurable. Another estimated variable is the moisture content, which is only "measurable" during steady-state operations of the coal mill. Instead, this paper suggests a method where these unknown variables are estimated based on a simple energy...

  6. One-dimensional scanning of moisture in heated porous building materials with NMR.

    Science.gov (United States)

    van der Heijden, G H A; Huinink, H P; Pel, L; Kopinga, K

    2011-02-01

    In this paper we present a new dedicated NMR setup which is capable of measuring one-dimensional moisture profiles in heated porous materials. The setup, which is placed in the bore of a 1.5 T whole-body scanner, is capable of reaching temperatures up to 500 °C. Moisture and temperature profiles can be measured quasi simultaneously with a typical time resolution of 2-5 min. A methodology is introduced for correcting temperature effects on NMR measurements at these elevated temperatures. The corrections are based on the Curie law for paramagnetism and the observed temperature dependence of the relaxation mechanisms occurring in porous materials. Both these corrections are used to obtain a moisture content profile from the raw NMR signal profile. To illustrate the methodology, a one-sided heating experiment of concrete with a moisture content in equilibrium with 97% RH is presented. This kind of heating experiment is of particular interest in the research on fire spalling of concrete, since it directly reveals the moisture and heat transport occurring inside the concrete. The obtained moisture profiles reveal a moisture peak building up behind the boiling front, resulting in a saturated layer. To our knowledge the direct proof of the formation of a moisture peak and subsequent moisture clogging has not been reported before. Copyright © 2010 Elsevier Inc. All rights reserved.

  7. Continuous data assimilation for downscaling large-footprint soil moisture retrievals

    KAUST Repository

    Altaf, M. U.

    2016-09-01

    Soil moisture is a crucial component of the hydrologic cycle, significantly influencing runoff, infiltration, recharge, evaporation and transpiration processes. Models characterizing these processes require soil moisture as an input, either directly or indirectly. Better characterization of the spatial variability of soil moisture leads to better predictions from hydrologic/climate models. In-situ measurements have fine resolution, but become impractical in terms of coverage over large extents. Remotely sensed data have excellent spatial coverage extents, but suffer from poorer spatial and temporal resolution. We present here an innovative approach to downscaling coarse resolution soil moisture data by combining data assimilation and physically based modeling. In this approach, we exploit the features of Continuous Data Assimilation (CDA). A nudging term, estimated as the misfit between interpolants of the assimilated coarse grid measurements and the fine grid model solution, is added to the model equations to constrain the model’s large scale variability by available measurements. Soil moisture fields generated at a fine resolution by a physically-based vadose zone model (e.g., HYDRUS) are subjected to data assimilation conditioned upon the coarse resolution observations. This enables nudging of the model outputs towards values that honor the coarse resolution dynamics while still being generated at the fine scale. The large scale features of the model output are constrained to the observations, and as a consequence, the misfit at the fine scale is reduced. The advantage of this approach is that fine resolution soil moisture maps can be generated across large spatial extents, given the coarse resolution data. The data assimilation approach also enables multi-scale data generation which is helpful to match the soil moisture input data to the corresponding modeling scale. Application of this approach is likely in generating fine and intermediate resolution soil

  8. Development of an Objective High Spatial Resolution Soil Moisture Index

    Science.gov (United States)

    Zavodsky, B.; Case, J.; White, K.; Bell, J. R.

    2015-12-01

    Drought detection, analysis, and mitigation has become a key challenge for a diverse set of decision makers, including but not limited to operational weather forecasters, climatologists, agricultural interests, and water resource management. One tool that is heavily used is the United States Drought Monitor (USDM), which is derived from a complex blend of objective data and subjective analysis on a state-by-state basis using a variety of modeled and observed precipitation, soil moisture, hydrologic, and vegetation and crop health data. The NASA Short-term Prediction Research and Transition (SPoRT) Center currently runs a real-time configuration of the Noah land surface model (LSM) within the NASA Land Information System (LIS) framework. The LIS-Noah is run at 3-km resolution for local numerical weather prediction (NWP) and situational awareness applications at select NOAA/National Weather Service (NWS) forecast offices over the Continental U.S. (CONUS). To enhance the practicality of the LIS-Noah output for drought monitoring and assessing flood potential, a 30+-year soil moisture climatology has been developed in an attempt to place near real-time soil moisture values in historical context at county- and/or watershed-scale resolutions. This LIS-Noah soil moisture climatology and accompanying anomalies is intended to complement the current suite of operational products, such as the North American Land Data Assimilation System phase 2 (NLDAS-2), which are generated on a coarser-resolution grid that may not capture localized, yet important soil moisture features. Daily soil moisture histograms are used to identify the real-time soil moisture percentiles at each grid point according to the county or watershed in which the grid point resides. Spatial plots are then produced that map the percentiles as proxies to the different USDM categories. This presentation will highlight recent developments of this gridded, objective soil moisture index, comparison to subjective

  9. Improving Simulated Soil Moisture Fields Through Assimilation of AMSR-E Soil Moisture Retrievals with an Ensemble Kalman Filter and a Mass Conservation Constraint

    Science.gov (United States)

    Li, Bailing; Toll, David; Zhan, Xiwu; Cosgrove, Brian

    2011-01-01

    Model simulated soil moisture fields are often biased due to errors in input parameters and deficiencies in model physics. Satellite derived soil moisture estimates, if retrieved appropriately, represent the spatial mean of soil moisture in a footprint area, and can be used to reduce model bias (at locations near the surface) through data assimilation techniques. While assimilating the retrievals can reduce model bias, it can also destroy the mass balance enforced by the model governing equation because water is removed from or added to the soil by the assimilation algorithm. In addition, studies have shown that assimilation of surface observations can adversely impact soil moisture estimates in the lower soil layers due to imperfect model physics, even though the bias near the surface is decreased. In this study, an ensemble Kalman filter (EnKF) with a mass conservation updating scheme was developed to assimilate the actual value of Advanced Microwave Scanning Radiometer (AMSR-E) soil moisture retrievals to improve the mean of simulated soil moisture fields by the Noah land surface model. Assimilation results using the conventional and the mass conservation updating scheme in the Little Washita watershed of Oklahoma showed that, while both updating schemes reduced the bias in the shallow root zone, the mass conservation scheme provided better estimates in the deeper profile. The mass conservation scheme also yielded physically consistent estimates of fluxes and maintained the water budget. Impacts of model physics on the assimilation results are discussed.

  10. Effects of neutron source type on soil moisture measurement

    Science.gov (United States)

    Irving Goldberg; Norman A. MacGillivray; Robert R. Ziemer

    1967-01-01

    A number of radioisotopes have recently become commercially available as alternatives to radium-225 in moisture gauging devices using alpha-neutron sources for determining soil moisture, for well logging, and for other industrial applications in which hydrogenous materials are measured.

  11. Determination of the moisture capacity of porous building materials

    NARCIS (Netherlands)

    Carmeliet, J.

    2002-01-01

    The moisture capacity, which is required to solve the isothermal moisture transport equation, is generally expressed by parametric functions covering both the hygroscopic and over-hygroscopic regime. The modality or number of analytical functions needed to describe the corresponding pore volume

  12. Using soil moisture forecasts for sub-seasonal summer temperature predictions in Europe

    Science.gov (United States)

    Orth, René; Seneviratne, Sonia I.

    2014-12-01

    Soil moisture exhibits outstanding memory characteristics and plays a key role within the climate system. Especially through its impacts on the evapotranspiration of soils and plants, it may influence the land energy balance and therefore surface temperature. These attributes make soil moisture an important variable in the context of weather and climate forecasting. In this study we investigate the value of (initial) soil moisture information for sub-seasonal temperature forecasts. For this purpose we employ a simple water balance model to infer soil moisture from streamflow observations in 400 catchments across Europe. Running this model with forecasted atmospheric forcing, we derive soil moisture forecasts, which we then translate into temperature forecasts using simple linear relationships. The resulting temperature forecasts show skill beyond climatology up to 2 weeks in most of the considered catchments. Even if forecasting skills are rather small at longer lead times with significant skill only in some catchments at lead times of 3 and 4 weeks, this soil moisture-based approach shows local improvements compared to the monthly European Centre for Medium Range Weather Forecasting (ECMWF) temperature forecasts at these lead times. For both products (soil moisture-only forecast and ECMWF forecast), we find comparable or better forecast performance in the case of extreme events, especially at long lead times. Even though a product based on soil moisture information alone is not of practical relevance, our results indicate that soil moisture (memory) is a potentially valuable contributor to temperature forecast skill. Investigating the underlying soil moisture of the ECMWF forecasts we find good agreement with the simple model forecasts, especially at longer lead times. Analyzing the drivers of the temperature forecast skills we find that they are mainly controlled by the strengths of (1) the soil moisture-temperature coupling and (2) the soil moisture memory. We

  13. Highly Efficient Moisture-Triggered Nanogenerator Based on Graphene Quantum Dots.

    Science.gov (United States)

    Huang, Yaxin; Cheng, Huhu; Shi, Gaoquan; Qu, Liangti

    2017-11-08

    A high-performance moisture triggered nanogenerator is fabricated by using graphene quantum dots (GQDs) as the active material. GQDs are prepared by direct oxidation and etching of natural graphite powder, which have small sizes of 2-5 nm and abundant oxygen-containing functional groups. After the treatment by electrochemical polarization, the GQDs-based moisture triggered nanogenerator can deliver a high voltage up to 0.27 V under 70% relative humidity variation, and a power density of 1.86 mW cm -2 with an optimized load resistor. The latter value is much higher than the moisture-electric power generators reported previously. The GQD moisture triggered nanogenerator is promising for self-power electronics and miniature sensors.

  14. On the assimilation of satellite derived soil moisture in numerical weather prediction models

    Science.gov (United States)

    Drusch, M.

    2006-12-01

    Satellite derived surface soil moisture data sets are readily available and have been used successfully in hydrological applications. In many operational numerical weather prediction systems the initial soil moisture conditions are analysed from the modelled background and 2 m temperature and relative humidity. This approach has proven its efficiency to improve surface latent and sensible heat fluxes and consequently the forecast on large geographical domains. However, since soil moisture is not always related to screen level variables, model errors and uncertainties in the forcing data can accumulate in root zone soil moisture. Remotely sensed surface soil moisture is directly linked to the model's uppermost soil layer and therefore is a stronger constraint for the soil moisture analysis. Three data assimilation experiments with the Integrated Forecast System (IFS) of the European Centre for Medium-range Weather Forecasts (ECMWF) have been performed for the two months period of June and July 2002: A control run based on the operational soil moisture analysis, an open loop run with freely evolving soil moisture, and an experimental run incorporating bias corrected TMI (TRMM Microwave Imager) derived soil moisture over the southern United States through a nudging scheme using 6-hourly departures. Apart from the soil moisture analysis, the system setup reflects the operational forecast configuration including the atmospheric 4D-Var analysis. Soil moisture analysed in the nudging experiment is the most accurate estimate when compared against in-situ observations from the Oklahoma Mesonet. The corresponding forecast for 2 m temperature and relative humidity is almost as accurate as in the control experiment. Furthermore, it is shown that the soil moisture analysis influences local weather parameters including the planetary boundary layer height and cloud coverage. The transferability of the results to other satellite derived soil moisture data sets will be discussed.

  15. Reconstructions of Soil Moisture for the Upper Colorado River Basin Using Tree-Ring Chronologies

    Science.gov (United States)

    Tootle, G.; Anderson, S.; Grissino-Mayer, H.

    2012-12-01

    Soil moisture is an important factor in the global hydrologic cycle, but existing reconstructions of historic soil moisture are limited. Tree-ring chronologies (TRCs) were used to reconstruct annual soil moisture in the Upper Colorado River Basin (UCRB). Gridded soil moisture data were spatially regionalized using principal components analysis and k-nearest neighbor techniques. Moisture sensitive tree-ring chronologies in and adjacent to the UCRB were correlated with regional soil moisture and tested for temporal stability. TRCs that were positively correlated and stable for the calibration period were retained. Stepwise linear regression was applied to identify the best predictor combinations for each soil moisture region. The regressions explained 42-78% of the variability in soil moisture data. We performed reconstructions for individual soil moisture grid cells to enhance understanding of the disparity in reconstructive skill across the regions. Reconstructions that used chronologies based on ponderosa pines (Pinus ponderosa) and pinyon pines (Pinus edulis) explained increased variance in the datasets. Reconstructed soil moisture was standardized and compared with standardized reconstructed streamflow and snow water equivalent from the same region. Soil moisture reconstructions were highly correlated with streamflow and snow water equivalent reconstructions, indicating reconstructions of soil moisture in the UCRB using TRCs successfully represent hydrologic trends, including the identification of periods of prolonged drought.

  16. Determining moisture content in pasta by vibrational spectroscopy.

    Science.gov (United States)

    Czaja, Tomasz; Kuzawińska, Ewelina; Sobota, Aldona; Szostak, Roman

    2018-02-01

    Pasta aside from bread is the most consumed cereal-based product in the world. Its taste and cooking ease makes it the basis of many cuisines. The pasta dough formed by mixing flour and water is extruded through an extrusion die to mould the appropriate pasta form and is dried to obtain a stable product. The concentration of moisture in the pasta dough is a one of key parameters determining the final quality of the product. Monitoring the moisture content of pasta after extrusion is also critically important. It enables a selection of suitable drying conditions that ensure the appropriate parameters of pasta, such as texture, color and taste, are met. A method for the quantitative determination of moisture content in pasta dough and in pasta based on the partial least squares treatment of infrared spectra registered using a single-reflection attenuated total reflectance diamond accessory is described. Results of a similar quality were found using models derived from near infrared spectra obtained in a diffuse reflectance mode and slightly worse based on Raman spectra. Relative standard errors of prediction calculated for moisture quantification by ATR/NIR/Raman techniques amounted to 2.54/3.16/5.56% and 2.15/3.32/5.67%, for calibration and validation sets, respectively. The proposed procedures can be used for fast and efficient pasta moisture quantification and may replace the current, more laborious methods used. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Length and time scales of atmospheric moisture recycling

    Directory of Open Access Journals (Sweden)

    R. J. van der Ent

    2011-03-01

    Full Text Available It is difficult to quantify the degree to which terrestrial evaporation supports the occurrence of precipitation within a certain study region (i.e. regional moisture recycling due to the scale- and shape-dependence of regional moisture recycling ratios. In this paper we present a novel approach to quantify the spatial and temporal scale of moisture recycling, independent of the size and shape of the region under study. In contrast to previous studies, which essentially used curve fitting, the scaling laws presented by us follow directly from the process equation. thus allowing a fair comparison between regions and seasons. The calculation is based on ERA-Interim reanalysis data for the period 1999 to 2008. It is shown that in the tropics or in mountainous terrain the length scale of recycling can be as low as 500 to 2000 km. In temperate climates the length scale is typically between 3000 to 5000 km whereas it amounts to more than 7000 km in desert areas. The time scale of recycling ranges from 3 to 20 days, with the exception of deserts, where it is much longer. The most distinct seasonal differences can be observed over the Northern Hemisphere: in winter, moisture recycling is insignificant, whereas in summer it plays a major role in the climate. The length and time scales of atmospheric moisture recycling can be useful metrics to quantify local climatic effects of land use change.

  18. Characterization of seeds with different moisture content by photoacoustic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez Pacheco, Arturo; Hernandez Aguilar, Claudia; Marinez Ortiz, Efrain [Instituto Politecnico Nacional, Sepi-Esime, Zacatenco. Unidad Profesional ' Adolfo Lopez Mateos' . Col. Lindavista. Mexico D.F., CP 07738 (Mexico); Cruz-Orea, Alfredo; Ayala-Maycotte, Esther, E-mail: fartur@hotmail.co [Departamento de Fisica, CINVESTAV - IPN, A. P. 14-740, Mexico D.F., C.P. 07360 (Mexico)

    2010-03-01

    Photoacoustic (PA) technique has important applications for material characterization and nondestructive evaluation of opaque solid materials. PA microscopy allows the acquisition of information of samples with inhomogeneous structures as agricultural seeds. A determining factor for seed safe storage is their moisture content. Seeds stored at high moisture content exhibit increased respiration, heating, and fungal invasion resulting in poor seed vigor and viability. Low moisture content, in the seed to be stored, is the best prevention for these problems. In this study, Photoacoustic Microscopy (PAM) was used to characterize seeds with different moisture content. In the PAM experimental setup the photoacoustic cell and its sensor, an electret microphone, are mounted on an x-y stage of mobile axes, with spatial resolution of 70 {mu}m. The excitation light source is a fiber coupled laser diode, at 650 nm wavelength, modulated in intensity at 1 Hz of frequency, by the reference oscillator of a lock-in amplifier. By using a microscope objective the laser beam was focused on the seed surface. The resolution was enough to obtain differences in the obtained images, which are dependent on the moisture content. This method, to study differences in the seed moisture content, is nondestructive and could be useful for a sustainable Agriculture.

  19. Unsaturated soil moisture drying and wetting diffusion coefficient measurements in the laboratory.

    Science.gov (United States)

    2009-09-01

    ABSTRACTTransient moisture flow in an unsaturated soil in response to suction changes is controlled by the unsaturated moisture diffusion coefficient. The moisture diffusion coefficient can be determined by measuring suction profiles over time. The l...

  20. Using high-resolution soil moisture modelling to assess the uncertainty of microwave remotely sensed soil moisture products at the correct spatial and temporal support

    Science.gov (United States)

    Wanders, N.; Karssenberg, D.; Bierkens, M. F. P.; Van Dam, J. C.; De Jong, S. M.

    2012-04-01

    Soil moisture is a key variable in the hydrological cycle and important in hydrological modelling. When assimilating soil moisture into flood forecasting models, the improvement of forecasting skills depends on the ability to accurately estimate the spatial and temporal patterns of soil moisture content throughout the river basin. Space-borne remote sensing may provide this information with a high temporal and spatial resolution and with a global coverage. Currently three microwave soil moisture products are available: AMSR-E, ASCAT and SMOS. The quality of these satellite-based products is often assessed by comparing them with in-situ observations of soil moisture. This comparison is however hampered by the difference in spatial and temporal support (i.e., resolution, scale), because the spatial resolution of microwave satellites is rather low compared to in-situ field measurements. Thus, the aim of this study is to derive a method to assess the uncertainty of microwave satellite soil moisture products at the correct spatial support. To overcome the difference in support size between in-situ soil moisture observations and remote sensed soil moisture, we used a stochastic, distributed unsaturated zone model (SWAP, van Dam (2000)) that is upscaled to the support of different satellite products. A detailed assessment of the SWAP model uncertainty is included to ensure that the uncertainty in satellite soil moisture is not overestimated due to an underestimation of the model uncertainty. We simulated unsaturated water flow up to a depth of 1.5m with a vertical resolution of 1 to 10 cm and on a horizontal grid of 1 km2 for the period Jan 2010 - Jun 2011. The SWAP model was first calibrated and validated on in-situ data of the REMEDHUS soil moisture network (Spain). Next, to evaluate the satellite products, the model was run for areas in the proximity of 79 meteorological stations in Spain, where model results were aggregated to the correct support of the satellite

  1. Moisture performance of building materials: From material characterization to building simulation using the Moisture Buffer Value concept

    Energy Technology Data Exchange (ETDEWEB)

    Abadie, Marc Olivier [Mechanical Engineering Graduate Program, Pontifical Catholic University of Parana, PUC-PR/CCET, Curitiba, PR 80215-901 (Brazil); LEPTAB, University of La Rochelle, La Rochelle, 17042 Cedex 1 (France); Mendonca, Katia Cordeiro [Mechanical Engineering Graduate Program, Pontifical Catholic University of Parana, PUC-PR/CCET, Curitiba, PR 80215-901 (Brazil)

    2009-02-15

    Predicting the indoor air relative humidity evolution is of great importance to evaluate people thermal comfort, perceived air quality and energy consumption. In building environments, porous materials of the envelope and furniture act on the indoor air humidity by reducing its variations. Solving the physical processes involved inside the porous materials requires the knowledge of the material hygrothermal properties that needs multiple and, for some of them, time-consuming experimental procedures. Recently, both the NORDTEST Project and Japanese Industrial Standard described a new Moisture Buffer Capacity index that accounts for surrounding air vapor concentration variation. The Moisture Buffer Value (MBV) indicates the amount of water vapor that is transported in or out of a material, during a certain period of time, when the vapor concentration of the surrounding air varies. The MBV evaluation requires only one experimental procedure and its value permits a direct comparison of the building materials moisture performance. However, two limitations can be distinguished: first, no relation between the MBV and the usual material hygrothermal properties has been clearly identified and second, no model has been proposed to actually use the MBV in building simulation. The present study aims to solve these two problems. First, the MBV fundamentals are introduced and discussed; followed by its relation with the usual material properties. Then, a lumped model for building simulation, whose parameters can be determined from the MBV experimental procedure, is described. To finish, examples of the use of this MBV-based lumped model for moisture prediction in buildings are presented. (author)

  2. An inverse moisture diffusion algorithm for the determination of diffusion coefficient

    Science.gov (United States)

    Jen Y. Liu; William T. Simpson; Steve P. Verrill

    2000-01-01

    The finite difference approximation is applied to estimate the moisture-dependent diffusion coefficient by utilizing test data of isothermal moisture desorption in northern red oak (Quercus rubra). The test data contain moisture distributions at discrete locations across the thickness of specimens, which coincides with the radial direction of northern red oak, and at...

  3. Moisture dependence of positron annihilation spectra in nylon-6

    International Nuclear Information System (INIS)

    Singh, J.J.; Clair, T.L.S.; Holt, W.H.; Mock, W. Jr.

    1984-01-01

    Positron annihilation time spectra have been measured in nylon-6 specimens as a function of their moisture content. The measured average longlife component lifetime values are: 1722 +- 47 ps (dry), 1676 +- 40 ps (14.6% saturation value), 1718 +- 26 ps (29.3% saturation value), 1720 +- 35 ps (50% of saturation value), 1857 +- 35 ps (78.1% of saturation value) and 1936 +- 57 ps (saturated). It is noted that the longlife component lifetime at first decreases and then increases with increasing moisture content in the specimens. This behavior is quite different from that observed in earlier studies of various epoxy, polyamide, and polyimide materials, where the longlife component lifetime decreased linearly with increasing moisture content. The longlife component intensity on the other hand, decreases steadily as the moisture content increases from 0 to 100% of the saturation value. A possible explanation for these anomalous features is discussed. (orig.)

  4. Soil moisture determination with Tesla NZK 203 neutron gage

    International Nuclear Information System (INIS)

    Hally, J.

    1977-01-01

    Soil moisture was measured using the NZK 203 neutron probe manufactured by Tesla Premysleni. The individual measuring sites were spaced at a distance of 100 m. The NZK 203 set consists of a NPK 202 moisture gage and a NSK 301 scintillation detector and features the following specifications: moisture density measuring range 20 to 500 kg/m 3 , 241 Am-Be fast neutron source having a neutron flux of 7.5x10 4 n.sec -1 +-10%, operating temperature -10 to +45 degC. The measured counting rate was primarily affected by the statistical fluctuation of ionizing radiation and by instrument instability. In order that these effects should be limited each measurement was repeated 10 times with the optimum measurement time at an interval of 20 to 100 sec. The NZK 203 Tesla set was proven to be suitable for rapid and reproducible determination of moisture profiles. (J.P.)

  5. A new model for predicting moisture uptake by packaged solid pharmaceuticals.

    Science.gov (United States)

    Chen, Y; Li, Y

    2003-04-14

    A novel mathematical model has been developed for predicting moisture uptake by packaged solid pharmaceutical products during storage. High density polyethylene (HDPE) bottles containing the tablet products of two new chemical entities and desiccants are investigated. Permeability of the bottles is determined at different temperatures using steady-state data. Moisture sorption isotherms of the two model drug products and desiccants at the same temperatures are determined and expressed in polynomial equations. The isotherms are used for modeling the time-humidity profile in the container, which enables the prediction of the moisture content of individual component during storage. Predicted moisture contents agree well with real time stability data. The current model could serve as a guide during packaging selection for moisture protection, so as to reduce the cost and cycle time of screening study.

  6. A system for measuring moisture transients in clay-based barrier materials

    International Nuclear Information System (INIS)

    Wan, A.W.L.; Kjartanson, B.H.; Spinney, M.H.; Radhakrishna, H.S.; Lau, K.C.

    1992-01-01

    This paper discusses the Buffer/Container Experiment which is one of the large-scale insitu experiments being conducted by AECL Research at its Underground Research Laboratory. The experiment is intended to examine the thermal-hydraulic-mechanical performance of sand-bentonite buffer material in a single emplacement borehole arrangement under in situ boundary conditions. Thermocouple psychrometers and thermal needles are being used as moisture sensors to track moisture transients in the buffer as the experiment progresses. Excitation and logging of the moisture sensors are largely automated. Procedures are being implemented to provide full automation of the moisture sensor system and to facilitate data conversion and management. Preliminary results from the Buffer/Container Experiment show that, up to five months after installation, the majority of the moisture sensors continue to function reliably

  7. Investigation on Tensile Strength Ratio (TSR Specimen to Predict Moisture Sensitivity of Asphalt Pavements Mixture and Using Polymer to Reduce Moisture Damage

    Directory of Open Access Journals (Sweden)

    Mohammed Aziz Hameed Al-Shaybani

    2017-05-01

    Full Text Available Moisture damage of asphalt concrete is defined as losing the strength and Permanence caused by the active presence of moisture.The most common technique to reduce moisture damage is using modifiers with the asphalt binder or the aggregate.The goal of this study was to explore the effect of various modifiers of polymer on the moisture susceptibility mixture of asphaltic concrete pavement. Modifiers included in this research selected two kinds of polymers Crumb Rubber No 50 (CR No 50 and Methyl Methacrylates (MMA(which are available in the local markets in Iraq and have been used in three percentages for each type. These percentages are (5, 10 and 15% for (CR No 50 and (2.5, 5 and 7.5(% for (MMA.Each type of these polymers is blended with asphalt by wet process at constant blending times for a suitable range of temperatures. The experimental works showed that all polymers modified mixtures have indirect tensile strength higher than control asphalt mixtures, its about (2-15 %, dependent on different type of polymer and polymer concentration under predicted suitable blending time.Test results of indirect tensile strength indicated betterment in modifying the proprieties of mixture, the increased resistance mixture of asphalt concrete pavement versus moisture damage, and reduced the effect of water on asphalt concrete properties. The final result is the addition of (10% CR No 50 and (5% MMA to asphalt mixtures showed an improved mixture of asphalt concrete properties and produced strong mixtures for road construction.One model is predicted for tensile strength ratio [TSR]to estimate the effects of polymer modification on moisture susceptibility mixture of asphalt concrete.

  8. Using a terrestrial laser scanner to measure spatiotemporal surface moisture dynamics

    Science.gov (United States)

    Smit, Y.; Donker, J.; Ruessink, G.

    2017-12-01

    A terrestrial laser scanner (TLS) is an active remote sensing technique that utilizes the round trip time of an emitted laser beam to provide the range between the laser scanner and the backscattering object. It is routinely used for topographic mapping, forest measurements or 3D city models since it derives useful object representations by means of a dense three-dimensional (3D) point cloud. Here, we present a novel application using the returned intensity of the emitted beam to detect surface moisture with the RIEGL VZ-400. Because this TLS operates at a wavelength near a water absorption band (1550 nm), reflectance is an accurate parameter to measure surface moisture over its full range. Five days of intensive laser scanning were performed on a Dutch beach to illustrate the applicability of the TLS. Concurrent gravimetric surface moisture samples were collected to calibrate the relation between reflectance and surface moisture. Results reveal the reflectance output is a robust parameter to measure surface moisture from the thin upper layer over its full range from 0% to 25%. The obtained calibration curve of the presented TLS, describing the relationship between reflectance and surface moisture, has a root-mean-square error of 2.7% and a correlation coefficient squared of 0.85. This relation holds to about 60 m from the TLS. Within this distance the TLS typically produces O(10^6-10^7) data points, which we averaged into surface moisture maps with a 1 x 1 m resolution. This grid size largely removes small moisture disturbances induced by, for example, footprints or tire tracks, while retaining larger scale trends. Concluding, TLS (RIEGL-VZ 400) is a highly suited technique to accurately and robustly measure spatiotemporal surface moisture variations on a coastal beach with high spatial ( 1 x 1 m) and temporal ( 15-30min.) resolution.

  9. Assimilation of SMOS Retrieved Soil Moisture into the Land Information System

    Science.gov (United States)

    Blankenship, Clay; Case, Jonathan; Zavodsky, Bradley; Jedlovec, Gary

    2014-01-01

    Soil moisture retrievals from the Soil Moisture and Ocean Salinity (SMOS) instrument are assimilated into the Noah land surface model (LSM) within the NASA Land Information System (LIS). Before assimilation, SMOS retrievals are bias-corrected to match the model climatological distribution using a Cumulative Distribution Function (CDF) matching approach. Data assimilation is done via the Ensemble Kalman Filter. The goal is to improve the representation of soil moisture within the LSM, and ultimately to improve numerical weather forecasts through better land surface initialization. We present a case study showing a large area of irrigation in the lower Mississippi River Valley, in an area with extensive rice agriculture. High soil moisture value in this region are observed by SMOS, but not captured in the forcing data. After assimilation, the model fields reflect the observed geographic patterns of soil moisture. Plans for a modeling experiment and operational use of the data are given. This work helps prepare for the assimilation of Soil Moisture Active/Passive (SMAP) retrievals in the near future.

  10. Moisture Transfer in Concrete: Numerical Determination of the Capillary Conductivity Coefficient

    Directory of Open Access Journals (Sweden)

    Simo Elie

    2017-03-01

    Full Text Available We numerically investigated moisture transfer in buildings made of concrete. We considered three types of concrete: normal concrete, pumice concrete and cellular concrete. We present the results of a 1-D liquid water flow in such materials. We evaluated the moisture distribution in building materials using the Runge-Kutta fourth-and-fifth-order method. The DOPRI5 code was used as an integrator. The model calculated the resulting moisture content and other moisture-dependent physical parameters. The moisture curves were plotted. The dampness data obtained was utilized for the numerical computation of the coefficient of the capillary conductivity of moisture. Different profiles of this coefficient are represented. Calculations were performed for four different values of the outdoor temperature: -5°C, 0°C, 5°C and 10°C. We determined that the curves corresponding to small time intervals of wetting are associated with great amplitudes of the capillary conductivity . The amplitudes of the coefficient of the capillary conductivity decrease as the time interval increases. High outdoor temperatures induce high amplitudes of the coefficient of the capillary conductivity.

  11. Wood preservative testing

    Science.gov (United States)

    Rebecca Ibach; Stan T. Lebow

    2012-01-01

    Most wood species used in commercial and residential construction have little natural biological durability and will suffer from biodeterioration when exposed to moisture. Historically, this problem has been overcome by treating wood for outdoor use with toxic wood preservatives. As societal acceptance of chemical use changes, there is continual pressure to develop and...

  12. Effects of moisture content on mechanical properties, transparency, and thermal stability of yuba film.

    Science.gov (United States)

    Zhang, Siran; Kim, Nayeon; Yokoyama, Wallace; Kim, Yookyung

    2018-03-15

    Yuba is the skin formed at the surface during the heating of soymilk. The 3rd, 7th, and 11th films were evaluated for properties at different RH. At 39% RH, the 11th film had the lowest moisture, while the 3rd film had the highest moisture. However, at 75% RH, reverse moisture results were obtained. The tensile strengths of the 3rd and 11th films were highest at 15% moisture, whereas the tensile strength of the 7th film was highest at 25% moisture. Elongation of the 3rd (127%) and 11th (85%) films were highest at 25% moisture. The light transmittance of the films was low and opaque at 5% moisture. The films were transparent at 23%-28% moisture, but became opaque as the moisture increased. The films at 39% RH (ΔH, 113-203J/g) had higher thermal stability than those at 87% RH (ΔH, 315-493J/g). Moisture content markedly changed the yuba film properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Robust design of microelectronics assemblies against mechanical shock, temperature and moisture effects of temperature, moisture and mechanical driving forces

    CERN Document Server

    Wong, E-H

    2015-01-01

    Robust Design of Microelectronics Assemblies Against Mechanical Shock, Temperature and Moisture discusses how the reliability of packaging components is a prime concern to electronics manufacturers. The text presents a thorough review of this important field of research, providing users with a practical guide that discusses theoretical aspects, experimental results, and modeling techniques. The authors use their extensive experience to produce detailed chapters covering temperature, moisture, and mechanical shock induced failure, adhesive interconnects, and viscoelasticity. Useful progr

  14. SHRINKAGE AND MOISTURE LOSS OF DRIED MELON SEEDS ...

    African Journals Online (AJOL)

    Samples of 100g clean, mature, freshly washed melon seeds were dried at intervals of 1/4, 1/2, 1 and 2h in an air-oven at 60O C. The experiments were carried out with five different bulk samples of melon seeds. The moisture content of the seeds at each drying stage was determined. The moisture loss in grams per ...

  15. A soil moisture and temperature network for SMOS validation in Western Denmark

    DEFF Research Database (Denmark)

    Bircher, Simone; Skou, Niels; Jensen, K. H.

    2011-01-01

    The Soil Moisture and Ocean Salinity Mission (SMOS) acquires surface soil moisture data globally, and thus product validation for a range of climate and environmental conditions across continents is a crucial step. For this purpose, a soil moisture and temperature network of Decagon ECH2O 5TE...... SMOS pixel (44 × 44 km), which is representative of the land surface conditions of the catchment and with minimal impact from open water (2) arrangement of three network clusters along the precipitation gradient, and (3) distribution of the stations according to respective fractions of classes...... representing the prevailing environmental conditions. Overall, measured moisture and temperature patterns could be related to the respective land cover and soil conditions. Texture-dependency of the 0–5 cm soil moisture measurements was demonstrated. Regional differences in 0–5 cm soil moisture, temperature...

  16. Relating coccidioidomycosis (valley fever) incidence to soil moisture conditions.

    Science.gov (United States)

    Coopersmith, E J; Bell, J E; Benedict, K; Shriber, J; McCotter, O; Cosh, M H

    2017-04-17

    Coccidioidomycosis (also called Valley fever) is caused by a soilborne fungus, Coccidioides spp. , in arid regions of the southwestern United States. Though some who develop infections from this fungus remain asymptomatic, others develop respiratory disease as a consequence. Less commonly, severe illness and death can occur when the infection spreads to other regions of the body. Previous analyses have attempted to connect the incidence of coccidioidomycosis to broadly available climatic measurements, such as precipitation or temperature. However, with the limited availability of long-term, in situ soil moisture data sets, it has not been feasible to perform a direct analysis of the relationships between soil moisture levels and coccidioidomycosis incidence on a larger temporal and spatial scale. Utilizing in situ soil moisture gauges throughout the southwest from the U.S. Climate Reference Network and a model with which to extend those estimates, this work connects periods of higher and lower soil moisture in Arizona and California between 2002 and 2014 to the reported incidence of coccidioidomycosis. The results indicate that in both states, coccidioidomycosis incidence is related to soil moisture levels from previous summers and falls. Stated differently, a higher number of coccidioidomycosis cases are likely to be reported if previous bands of months have been atypically wet or dry, depending on the location.

  17. Continuous data assimilation for downscaling large-footprint soil moisture retrievals

    KAUST Repository

    Altaf, M. U.; Jana, Raghavendra Belur; Hoteit, Ibrahim; McCabe, Matthew

    2016-01-01

    Soil moisture is a crucial component of the hydrologic cycle, significantly influencing runoff, infiltration, recharge, evaporation and transpiration processes. Models characterizing these processes require soil moisture as an input, either directly

  18. Global Soil Moisture from the Aquarius/SAC-D Satellite: Description and Initial Assessment

    Science.gov (United States)

    Bindlish, Rajat; Jackson, Thomas; Cosh, Michael; Zhao, Tianjie; O'Neil, Peggy

    2015-01-01

    Aquarius satellite observations over land offer a new resource for measuring soil moisture from space. Although Aquarius was designed for ocean salinity mapping, our objective in this investigation is to exploit the large amount of land observations that Aquarius acquires and extend the mission scope to include the retrieval of surface soil moisture. The soil moisture retrieval algorithm development focused on using only the radiometer data because of the extensive heritage of passive microwave retrieval of soil moisture. The single channel algorithm (SCA) was implemented using the Aquarius observations to estimate surface soil moisture. Aquarius radiometer observations from three beams (after bias/gain modification) along with the National Centers for Environmental Prediction model forecast surface temperatures were then used to retrieve soil moisture. Ancillary data inputs required for using the SCA are vegetation water content, land surface temperature, and several soil and vegetation parameters based on land cover classes. The resulting global spatial patterns of soil moisture were consistent with the precipitation climatology and with soil moisture from other satellite missions (Advanced Microwave Scanning Radiometer for the Earth Observing System and Soil Moisture Ocean Salinity). Initial assessments were performed using in situ observations from the U.S. Department of Agriculture Little Washita and Little River watershed soil moisture networks. Results showed good performance by the algorithm for these land surface conditions for the period of August 2011-June 2013 (rmse = 0.031 m(exp 3)/m(exp 3), Bias = -0.007 m(exp 3)/m(exp 3), and R = 0.855). This radiometer-only soil moisture product will serve as a baseline for continuing research on both active and combined passive-active soil moisture algorithms. The products are routinely available through the National Aeronautics and Space Administration data archive at the National Snow and Ice Data Center.

  19. Moisture migration in concrete. Final report. Technical report C-75-1

    International Nuclear Information System (INIS)

    McDonald, J.E.

    1975-05-01

    In an effort to obtain information regarding the nature of moisture movement and rate of moisture loss in a prestressed concrete reactor vessel (PCRV), an experimental study of moisture migration in a pie-shaped specimen representing the flow path through a cylindrical wall of a PCRV was initiated. After casting of the test specimen, temperature distribution, shrinkage, and moisture distribution were monitored for approximately 510 days. After this initial monitoring, a temperature difference of 80 0 F was applied to the specimen, and the above-mentioned measurements were continued for an additional test period of one year. Results indicate that moisture migration in thick sections of concrete, such as a PCRV, is a slow process and is not likely to be a significant factor with temperature differences of 80 0 F or less. 15 references. (auth)

  20. Integrating an embedded system in a microwave moisture meter

    Science.gov (United States)

    The conversion of a PC- or laptop-controlled microwave moisture meter to a stand-alone meter hosting its own embedded system is discussed. The moisture meter measures the attenuation and phase shift of low power microwaves traversing the sample, from which the dielectric properties are calculated. T...

  1. From laboratory corrosion tests to a corrosion lifetime for wood fasteners : progress and challenges

    Science.gov (United States)

    Samuel L. Zelinka; Dominique Derome; Samuel V. Glass

    2010-01-01

    Determining a “corrosion-lifetime” for fasteners embedded in wood treated with recently adopted preservative systems depends upon successfully relating results of laboratory tests to in-service conditions. In contrast to laboratory tests where metal is embedded in wood at constant temperature and moisture content, the in-service temperature and moisture content of wood...

  2. Thermal denaturation of sunflower globulins in low moisture conditions

    International Nuclear Information System (INIS)

    Rouilly, A.; Orliac, O.; Silvestre, F.; Rigal, L.

    2003-01-01

    DSC analysis in pressure resisting pans of sunflower oil cake makes appear the endothermic peak of sunflower globulins denaturation. Its temperature decreases from 189.5 to 119.9 deg. C while the corresponding enthalpy increases from 2.6 to 3.3 J/g of sample, or from 6.7 to 12.2 J/g of dry protein, when the samples moisture content varies from 0 to 30.0% of the total weight. The plot of the denaturation temperature versus the moisture content is not linear but has a rounded global shape and seems to follow the hydration behavior of the proteins, modeled with the sorption isotherm. As it can be seen on scanning electron microscopy (SEM) micrographs, protein corpuscles 'melt' after such a thermal treatment and large aggregates form by coagulation. Moisture dependence of the 'fusion' temperature of native proteic organization, in low moisture conditions, offers so a new characterization method for the use of vegetable proteins in agro-materials

  3. Thermal denaturation of sunflower globulins in low moisture conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rouilly, A.; Orliac, O.; Silvestre, F.; Rigal, L

    2003-03-05

    DSC analysis in pressure resisting pans of sunflower oil cake makes appear the endothermic peak of sunflower globulins denaturation. Its temperature decreases from 189.5 to 119.9 deg. C while the corresponding enthalpy increases from 2.6 to 3.3 J/g of sample, or from 6.7 to 12.2 J/g of dry protein, when the samples moisture content varies from 0 to 30.0% of the total weight. The plot of the denaturation temperature versus the moisture content is not linear but has a rounded global shape and seems to follow the hydration behavior of the proteins, modeled with the sorption isotherm. As it can be seen on scanning electron microscopy (SEM) micrographs, protein corpuscles 'melt' after such a thermal treatment and large aggregates form by coagulation. Moisture dependence of the 'fusion' temperature of native proteic organization, in low moisture conditions, offers so a new characterization method for the use of vegetable proteins in agro-materials.

  4. Distributed fiber optic moisture intrusion sensing system

    Science.gov (United States)

    Weiss, Jonathan D.

    2003-06-24

    Method and system for monitoring and identifying moisture intrusion in soil such as is contained in landfills housing radioactive and/or hazardous waste. The invention utilizes the principle that moist or wet soil has a higher thermal conductance than dry soil. The invention employs optical time delay reflectometry in connection with a distributed temperature sensing system together with heating means in order to identify discrete areas within a volume of soil wherein temperature is lower. According to the invention an optical element and, optionally, a heating element may be included in a cable or other similar structure and arranged in a serpentine fashion within a volume of soil to achieve efficient temperature detection across a large area or three dimensional volume of soil. Remediation, moisture countermeasures, or other responsive action may then be coordinated based on the assumption that cooler regions within a soil volume may signal moisture intrusion where those regions are located.

  5. Anthropogenic warming exacerbates European soil moisture droughts

    Science.gov (United States)

    Samaniego, L.; Thober, S.; Kumar, R.; Wanders, N.; Rakovec, O.; Pan, M.; Zink, M.; Sheffield, J.; Wood, E. F.; Marx, A.

    2018-05-01

    Anthropogenic warming is anticipated to increase soil moisture drought in the future. However, projections are accompanied by large uncertainty due to varying estimates of future warming. Here, using an ensemble of hydrological and land-surface models, forced with bias-corrected downscaled general circulation model output, we estimate the impacts of 1-3 K global mean temperature increases on soil moisture droughts in Europe. Compared to the 1.5 K Paris target, an increase of 3 K—which represents current projected temperature change—is found to increase drought area by 40% (±24%), affecting up to 42% (±22%) more of the population. Furthermore, an event similar to the 2003 drought is shown to become twice as frequent; thus, due to their increased occurrence, events of this magnitude will no longer be classified as extreme. In the absence of effective mitigation, Europe will therefore face unprecedented increases in soil moisture drought, presenting new challenges for adaptation across the continent.

  6. Equivalent circuit modeling of the dielectric properties of rubber wood at low frequency

    Science.gov (United States)

    Wan M. Daud; Kaida B. Khalid; Aziz H.A. Sidek

    2000-01-01

    Dielectric properties of rubber wood were studied at various moisture contents and grain directions at low frequencies from 10-2 to 105 Hz. Results showed that the moisture content of wood affected the dielectric properties considerably. Dielectric data at different anisotropic directions, i.e., longitudinal, radial, and...

  7. Quantifying soil moisture impacts on light use efficiency across biomes.

    Science.gov (United States)

    Stocker, Benjamin D; Zscheischler, Jakob; Keenan, Trevor F; Prentice, I Colin; Peñuelas, Josep; Seneviratne, Sonia I

    2018-06-01

    Terrestrial primary productivity and carbon cycle impacts of droughts are commonly quantified using vapour pressure deficit (VPD) data and remotely sensed greenness, without accounting for soil moisture. However, soil moisture limitation is known to strongly affect plant physiology. Here, we investigate light use efficiency, the ratio of gross primary productivity (GPP) to absorbed light. We derive its fractional reduction due to soil moisture (fLUE), separated from VPD and greenness changes, using artificial neural networks trained on eddy covariance data, multiple soil moisture datasets and remotely sensed greenness. This reveals substantial impacts of soil moisture alone that reduce GPP by up to 40% at sites located in sub-humid, semi-arid or arid regions. For sites in relatively moist climates, we find, paradoxically, a muted fLUE response to drying soil, but reduced fLUE under wet conditions. fLUE identifies substantial drought impacts that are not captured when relying solely on VPD and greenness changes and, when seasonally recurring, are missed by traditional, anomaly-based drought indices. Counter to common assumptions, fLUE reductions are largest in drought-deciduous vegetation, including grasslands. Our results highlight the necessity to account for soil moisture limitation in terrestrial primary productivity data products, especially for drought-related assessments. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

  8. Development and Performance Evaluation of a Re-Circulatory Vegetable Moisturizer

    Directory of Open Access Journals (Sweden)

    M. O. Sunmonu

    2016-08-01

    Full Text Available A re-circulatory vegetable moisturizer for preventing wilting in vegetables was developed and its performance evaluation carried out. Freshly harvested Amaranthus vegetables were used for the experiments. The temperature and relative humidity were monitored daily. The vitamin A of this produce was determined at intervals of two days for 9 days. The effects of the storage parameters (temperature and relative humidity on the nutritional value of the produce were determined using statistical analysis of variance (ANOVA. Further analysis by Duncan’s New Multiple Range Test (DNMRT was carried out to compare the means. The vegetable moisturizer was evaluated by comparing the change in nutritional (vitamin A of Amaranthus vegetable with hand wetting system and no wetting condition. The results showed that the moisturizer had higher mean vitamin A content (4.93mg/100gcompared to the mean vitamin A content of the manual wetting (4.88mg/100g and no wetting condition (4.57mg/100g. The sensory characteristics showed that the Moisturizer was more desirable when compared to the manual wetting and no wetting condition after nine days. It was concluded that the Moisturizer preserved the nutritional and sensory characteristics (texture and colour better than the manual and no wetting condition as a result of lower temperature, higher relative humidity and better water draining of the Moisturizer.

  9. Assessment of Multi-frequency Electromagnetic Induction for Determining Soil Moisture Patterns at the Hillslope Scale

    Science.gov (United States)

    Tromp-van Meerveld, I.; McDonnell, J.

    2009-05-01

    We present an assessment of electromagnetic induction (EM) as a potential rapid and non-invasive method to map soil moisture patterns at the Panola (GA, USA) hillslope. We address the following questions regarding the applicability of EM measurements for hillslope hydrological investigations: (1) Can EM be used for soil moisture measurements in areas with shallow soils?; (2) Can EM represent the temporal and spatial patterns of soil moisture throughout the year?; and (3) can multiple frequencies be used to extract additional information content from the EM approach and explain the depth profile of soil moisture? We found that the apparent conductivity measured with the multi-frequency GEM-300 was linearly related to soil moisture measured with an Aqua-pro capacitance sensor below a threshold conductivity and represented the temporal patterns in soil moisture well. During spring rainfall events that wetted only the surface soil layers the apparent conductivity measurements explained the soil moisture dynamics at depth better than the surface soil moisture dynamics. All four EM frequencies (7290, 9090, 11250, and 14010 Hz) were highly correlated and linearly related to each other and could be used to predict soil moisture. This limited our ability to use the four different EM frequencies to obtain a soil moisture profile with depth. The apparent conductivity patterns represented the observed spatial soil moisture patterns well when the individually fitted relationships between measured soil moisture and apparent conductivity were used for each measurement point. However, when the same (master) relationship was used for all measurement locations, the soil moisture patterns were smoothed and did not resemble the observed soil moisture patterns very well. In addition, the range in calculated soil moisture values was reduced compared to observed soil moisture. Part of the smoothing was likely due to the much larger measurement area of the GEM-300 compared to the Aqua

  10. Mechanisms of deterioration of intermediate moisture food systems

    Science.gov (United States)

    Labuza, T. P.

    1972-01-01

    A study of shelf stability in intermediate moisture foods was made. Major efforts were made to control lipid oxidation and nonenzymatic browning. In order to determine means of preventing these reactions, model systems were developed having the same water activity content relationship of intermediate moisture foods. Models were based on a cellulose-lipid and protein-lipid system with glycerol added as the humectant. Experiments with both systems indicate that lipid oxidation is promoted significantly in the intermediate moisture range. The effect appeared to be related to increased mobility of either reactants or catalysts, since when the amount of water in the system reached a level where capillary condensation occurred and thus free water was present, the rates of oxidation increased. With added glycerol, which is water soluble and thus increases the amount of mobile phase, the increase in oxidation rate occurs at a lower relative humidity. The rates of oxidation were maximized at 61% RH and decreased again at 75% RH probably due to dilution. No significant non-enzymatic browning occurred in the protein-lipid systems. Prevention of oxidation by the use of metal chelating agents was enhanced in the cellulose system, whereas, with protein present, the lipid soluble chain terminating antioxidants (such as BHA) worked equally as well. Preliminary studies of foods adjusted to the intermediate moisture range bear out the results of oxidation in model systems. It can be concluded that for most fat containing intermediate moisture foods, rancidity will be the reaction most limiting stability.

  11. Correlation between near infrared spectroscopy and electrical techniques in measuring skin moisture content

    International Nuclear Information System (INIS)

    Mohamad, M; Sabbri, A R M; Jafri, M Z Mat; Omar, A F

    2014-01-01

    Near infrared (NIR) spectroscopy technique serves as an important tool for the measurement of moisture content of skin owing to the advantages it has over the other techniques. The purpose of the study is to develop a correlation between NIR spectrometer with electrical conventional techniques for skin moisture measurement. A non-invasive measurement of moisture content of skin was performed on different part of human face and hand under control environment (temperature 21 ± 1 °C, relative humidity 45 ± 5 %). Ten healthy volunteers age between 21-25 (male and female) participated in this study. The moisture content of skin was measured using DermaLab ® USB Moisture Module, Scalar Moisture Checker and NIR spectroscopy (NIRQuest). Higher correlation was observed between NIRQuest and Dermalab moisture probe with a coefficient of determination (R 2 ) above 70 % for all the subjects. However, the value of R 2 between NIRQuest and Moisture Checker was observed to be lower with the R 2 values ranges from 51.6 to 94.4 %. The correlation of NIR spectroscopy technique successfully developed for measuring moisture content of the skin. The analysis of this correlation can help to establish novel instruments based on an optical system in clinical used especially in the dermatology field

  12. Response of maize ( Zea mays L.) to varied moisture levels under ...

    African Journals Online (AJOL)

    Laboratory and glasshouse trials were used to determine the response of maize plants to varied moisture levels under Striga lutea infestation. Six moisture levels (1.5, 2.0, 2.5, 3.0, 3.5 and 4.0 ml) were applied to striga seed for germination count in the laboratory, while five moisture levels (300, 600, 900, 1200 and 1500 ml) ...

  13. Measurement of moisture depth distribution in composite materials using positron lifetime technique

    International Nuclear Information System (INIS)

    Singh, J.J.; Holt, W.H.; Mock, W. Jr.; Mall, G.H.

    1980-01-01

    Fiber-reinforced resin matrix composites reportedly suffer significant degradation in their mechanical properties when exposed to hot, moist, environments for extended periods. Moisture weakens the fiber matrix bond as well as the matrix shear strength. An important factor in determining the extent of degradation is the depth distribution of moisture in the resin matrix. Despite the importance of measuring moisture distribution and its effects on composite material properties, not enough data are available on suitable nondestructive techniques for detecting and measuring moisture diffusion in organic composite materials. This paper addresses itself to the problem of measuring the moisture content of such materials, with special emphasis on its depth distribution, using positron lifetime technique

  14. Inversion of Farmland Soil Moisture in Large Region Based on Modified Vegetation Index

    Science.gov (United States)

    Wang, J. X.; Yu, B. S.; Zhang, G. Z.; Zhao, G. C.; He, S. D.; Luo, W. R.; Zhang, C. C.

    2018-04-01

    Soil moisture is an important parameter for agricultural production. Efficient and accurate monitoring of soil moisture is an important link to ensure the safety of agricultural production. Remote sensing technology has been widely used in agricultural moisture monitoring because of its timeliness, cyclicality, dynamic tracking of changes in things, easy access to data, and extensive monitoring. Vegetation index and surface temperature are important parameters for moisture monitoring. Based on NDVI, this paper introduces land surface temperature and average temperature for optimization. This article takes the soil moisture in winter wheat growing area in Henan Province as the research object, dividing Henan Province into three main regions producing winter wheat and dividing the growth period of winter wheat into the early, middle and late stages on the basis of phenological characteristics and regional characteristics. Introducing appropriate correction factor during the corresponding growth period of winter wheat, correcting the vegetation index in the corresponding area, this paper establishes regression models of soil moisture on NDVI and soil moisture on modified NDVI based on correlation analysis and compare models. It shows that modified NDVI is more suitable as a indicator of soil moisture because of the better correlation between soil moisture and modified NDVI and the higher prediction accuracy of the regression model of soil moisture on modified NDVI. The research in this paper has certain reference value for winter wheat farmland management and decision-making.

  15. Surface Soil Moisture Memory Estimated from Models and SMAP Observations

    Science.gov (United States)

    He, Q.; Mccoll, K. A.; Li, C.; Lu, H.; Akbar, R.; Pan, M.; Entekhabi, D.

    2017-12-01

    Soil moisture memory(SMM), which is loosely defined as the time taken by soil to forget an anomaly, has been proved to be important in land-atmosphere interaction. There are many metrics to calculate the SMM timescale, for example, the timescale based on the time-series autocorrelation, the timescale ignoring the soil moisture time series and the timescale which only considers soil moisture increment. Recently, a new timescale based on `Water Cycle Fraction' (Kaighin et al., 2017), in which the impact of precipitation on soil moisture memory is considered, has been put up but not been fully evaluated in global. In this study, we compared the surface SMM derived from SMAP observations with that from land surface model simulations (i.e., the SMAP Nature Run (NR) provided by the Goddard Earth Observing System, version 5) (Rolf et al., 2014). Three timescale metrics were used to quantify the surface SMM as: T0 based on the soil moisture time series autocorrelation, deT0 based on the detrending soil moisture time series autocorrelation, and tHalf based on the Water Cycle Fraction. The comparisons indicate that: (1) there are big gaps between the T0 derived from SMAP and that from NR (2) the gaps get small for deT0 case, in which the seasonality of surface soil moisture was removed with a moving average filter; (3) the tHalf estimated from SMAP is much closer to that from NR. The results demonstrate that surface SMM can vary dramatically among different metrics, while the memory derived from land surface model differs from the one from SMAP observation. tHalf, with considering the impact of precipitation, may be a good choice to quantify surface SMM and have high potential in studies related to land atmosphere interactions. References McColl. K.A., S.H. Alemohammad, R. Akbar, A.G. Konings, S. Yueh, D. Entekhabi. The Global Distribution and Dynamics of Surface Soil Moisture, Nature Geoscience, 2017 Reichle. R., L. Qing, D.L. Gabrielle, A. Joe. The "SMAP_Nature_v03" Data

  16. Analysis on the moment method for determining the moisture transport properties in porous media

    International Nuclear Information System (INIS)

    Wang, B.X.; Fang, Z.H.

    1987-01-01

    The authors discuss a new unsteady-state method proposed for determining the moisture transport properties in wet porous media. It is based on measurement of the change in moment of gravity caused by the moisture migration. In addition to its high-speed performance, this method may get rid of the difficulty in determination of a changing moisture content or moisture distribution. On this basis, two particular procedures are contrived: a constant heat source method for determining the thermal mass diffusivity and an instantaneous moisture source method for determining the moisture diffusivity

  17. Potential of bias correction for downscaling passive microwave and soil moisture data

    Science.gov (United States)

    Passive microwave satellites such as SMOS (Soil Moisture and Ocean Salinity) or SMAP (Soil Moisture Active Passive) observe brightness temperature (TB) and retrieve soil moisture at a spatial resolution greater than most hydrological processes. Bias correction is proposed as a simple method to disag...

  18. Moisture diffusion and permeability characteristics of hydroxypropylmethylcellulose and hard gelatin capsules.

    Science.gov (United States)

    Barham, Ahmad S; Tewes, Frederic; Healy, Anne Marie

    2015-01-30

    The primary objective of this paper is to compare the sorption characteristics of hydroxypropylmethylcellulose (HPMC) and hard gelatin (HG) capsules and their ability to protect capsule contents. Moisture sorption and desorption isotherms for empty HPMC and HG capsules have been investigated using dynamic vapour sorption (DVS) at 25°C. All sorption studies were analysed using the Young-Nelson model equations which distinguishes three moisture sorption types: monolayer adsorption moisture, condensation and absorption. Water vapour diffusion coefficients (D), solubility (S) and permeability (P) parameters of the capsule shells were calculated. ANOVA was performed with the Tukey comparison test to analyse the effect of %RH and capsule type on S, P, and D parameters. The moisture uptake of HG capsules were higher than HPMC capsules at all %RH conditions studied. It was found that values of D and P across HPMC capsules were greater than for HG capsules at 0-40 %RH; whereas over the same %RH range S values were higher for HG than for HPMC capsules. S values decreased gradually as the %RH was increased up to 60% RH. To probe the effect of moisture ingress, spray dried lactose was loaded into capsules. Phase evolution was characterised by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and differential scanning calorimetry (DSC). The capsules under investigation are not capable of protecting spray dried lactose from induced solid state changes as a result of moisture uptake. For somewhat less moisture sensitive formulations, HPMC would appear to be a better choice than HG in terms of protection of moisture induced deterioration. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Time domain reflectometry measured moisture content of sewage sludge compost across temperatures.

    Science.gov (United States)

    Cai, Lu; Chen, Tong-Bin; Gao, Ding; Liu, Hong-Tao; Chen, Jun; Zheng, Guo-Di

    2013-01-01

    Time domain reflectometry (TDR) is a prospective measurement technology for moisture content of sewage sludge composting material; however, a significant dependence upon temperature has been observed. The objective of this study was to assess the impacts of temperature upon moisture content measurement and determine if TDR could be used to monitor moisture content in sewage sludge compost across a range of temperatures. We also investigated the combined effects of temperature and conductivity on moisture content measurement. The results revealed that the moisture content of composting material could be determined by TDR using coated probes, even when the measured material had a moisture content of 0.581 cm(3)cm(-3), temperature of 70°C and conductivity of 4.32 mS cm(-1). TDR probes were calibrated as a function of dielectric properties that included temperature effects. When the bulk temperature varied from 20°C to 70°C, composting material with 0.10-0.70 cm(3)cm(-3) moisture content could be measured by TDR using coated probes, and calibrations based on different temperatures minimized the errors. Copyright © 2012. Published by Elsevier Ltd.

  20. Assimilation of microwave brightness temperatures for soil moisture estimation using particle filter

    International Nuclear Information System (INIS)

    Bi, H Y; Ma, J W; Qin, S X; Zeng, J Y

    2014-01-01

    Soil moisture plays a significant role in global water cycles. Both model simulations and remote sensing observations have their limitations when estimating soil moisture on a large spatial scale. Data assimilation (DA) is a promising tool which can combine model dynamics and remote sensing observations to obtain more precise ground soil moisture distribution. Among various DA methods, the particle filter (PF) can be applied to non-linear and non-Gaussian systems, thus holding great potential for DA. In this study, a data assimilation scheme based on the residual resampling particle filter (RR-PF) was developed to assimilate microwave brightness temperatures into the macro-scale semi-distributed Variance Infiltration Capacity (VIC) Model to estimate surface soil moisture. A radiative transfer model (RTM) was used to link brightness temperatures with surface soil moisture. Finally, the data assimilation scheme was validated by experimental data obtained at Arizona during the Soil Moisture Experiment 2004 (SMEX04). The results show that the estimation accuracy of soil moisture can be improved significantly by RR-PF through assimilating microwave brightness temperatures into VIC model. Both the overall trends and specific values of the assimilation results are more consistent with ground observations compared with model simulation results

  1. Concentrations of tritium in atmospheric moisture and precipitation of Mt. Hakkoda

    International Nuclear Information System (INIS)

    Kimura, Hideki; Kon, Takezumi; Sasaki, Mamoru

    2000-01-01

    A large-scale spent nuclear fuel reprocessing plant in Japan is now under construction in Rokkasho Village, Aomori Prefecture. The 3 H will be one of the major radionuclides released from the plant. To grasp the behavior of 3 H in the environment in Aomori Prefecture, we surveyed 3 H concentrations in the atmospheric moisture and the precipitation samples at Mt. Hakkoda. Additional atmospheric moisture samples were collected at Rokkasho Village and Aomori City. The relatively high 3 H concentration in the atmospheric moisture and the precipitation samples at Mt. Hakkoda were observed from spring to summer. The 3 H concentrations in the precipitation were similar to those in the atmospheric moisture. The temporal variation patterns of 3 H concentrations in the atmospheric moisture were similar in relatively wide region that covers from Mt. Hakkoda to Aomori City and Rokkasho Village. The 3 H concentration in atmospheric moisture at the top of Mt. Hakkoda positively correlated with the ozone concentration. It suggested that 3 H originated from the stratosphere, and showed that ozone might be used as an indictor of background 3 H. (author)

  2. Improvement of water resistance and dimensional stability of wood through titanium dioxide coating

    Science.gov (United States)

    Qingfeng Sun; Haipeng Yu; Yixing Liu; Jian Li; Yun Lu; John F. Hunt

    2010-01-01

    Moisture absorption and dimensional distortion are the major drawbacks of wood utilization as building material. In this study, poplar wood coated with a thin layer of titanium dioxide (TiO2) was prepared by the cosolvent-controlled hydrothermal method. Subsequently, its moisture absorption and dimensional stability were examined. Scanning...

  3. Shelf stable intermediate moisture fruit cubes using radiation technology

    International Nuclear Information System (INIS)

    Mishra, Bibhuti B.; Saxena, Sudhanshu; Gautam, Satyendra; Chander, Ramesh; Sharma, Arun

    2009-01-01

    A process has been developed to prepare shelf stable ready-to-eat (RTE) intermediate moisture pineapple slices and papaya cubes using radiation technology. The combination of hurdles including osmotic dehydration, blanching, infrared drying, and gamma radiation dose of 1 kGy successfully reduced the microbial load to below detectable limit. The shelf life of the intermediate moisture pineapple slices and papaya cubes was found to be 40 days at ambient temperature (28 ± 2 deg C). The control samples spoiled within 6 days. The RTE intermediate moisture fruit products were found to have good texture, colour and sensory acceptability during this 40 days storage. (author)

  4. Integrating an Embedded System within a Microwave Moisture Meter

    Science.gov (United States)

    In this paper, the conversion of a PC or laptop-controlled microwave moisture meter to a stand-alone meter hosting its own embedded system is discussed. The moisture meter uses low-power microwaves to measure the attenuation and phase shift of the sample, from which the dielectric properties are cal...

  5. A Technical Design Approach to Soil Moisture Content Measurement

    African Journals Online (AJOL)

    Soil moisture is an important type of data in many fields; ranging from agriculture to environmental monitoring. Three soil samples were collected at definite proportions to represent the three basic soil types (sandy, loamy and clay soils). The moisture contents of these soil samples were analyzed using the thermogravimetric ...

  6. A meta-analysis of the response of soil moisture to experimental warming

    International Nuclear Information System (INIS)

    Xu, Wenfang; Yuan, Wenping; Dong, Wenjie; Xia, Jiangzhou; Liu, Dan; Chen, Yang

    2013-01-01

    Soil moisture is an important variable for regulating carbon, water and energy cycles of terrestrial ecosystems. However, numerous inconsistent conclusions have been reported regarding the responses of soil moisture to warming. In this study, we conducted a meta-analysis for examination of the response of soil moisture to experimental warming across global warming sites including several ecosystem types. The results showed that soil moisture decreased in response to warming treatments when compared with control treatments in most ecosystem types. The largest reduction of soil moisture was observed in forests, while intermediate reductions were observed in grassland and cropland, and they were both larger than the reductions observed in shrubland and tundra ecosystems. Increases (or no change) in soil moisture also occurred in some ecosystems. Taken together, these results showed a trend of soil drying in most ecosystems, which may have exerted profound impacts on a variety of terrestrial ecosystem processes as well as feedbacks to the climate system. (letter)

  7. Elevated moisture stimulates carbon loss from mineral soils by releasing protected organic matter.

    Science.gov (United States)

    Huang, Wenjuan; Hall, Steven J

    2017-11-24

    Moisture response functions for soil microbial carbon (C) mineralization remain a critical uncertainty for predicting ecosystem-climate feedbacks. Theory and models posit that C mineralization declines under elevated moisture and associated anaerobic conditions, leading to soil C accumulation. Yet, iron (Fe) reduction potentially releases protected C, providing an under-appreciated mechanism for C destabilization under elevated moisture. Here we incubate Mollisols from ecosystems under C 3 /C 4 plant rotations at moisture levels at and above field capacity over 5 months. Increased moisture and anaerobiosis initially suppress soil C mineralization, consistent with theory. However, after 25 days, elevated moisture stimulates cumulative gaseous C-loss as CO 2 and CH 4 to >150% of the control. Stable C isotopes show that mineralization of older C 3 -derived C released following Fe reduction dominates C losses. Counter to theory, elevated moisture may significantly accelerate C losses from mineral soils over weeks to months-a critical mechanistic deficiency of current Earth system models.

  8. Effect of Root-Zone Moisture Variations on Growth of Lettuce and Pea Plants

    Science.gov (United States)

    Ilieva, Iliana; Ivanova, Tania

    2008-06-01

    Variations in substrate moisture lead to changes in water and oxygen availability to plant roots. Ground experiments were carried out in the laboratory prototype of SVET-2 Space Greenhouse to study the effect of variation of root-zone moisture conditions on growth of lettuce and pea plants. The effect of transient increase (for 1 day) and drastic increase (waterlogging for 10 days) of substrate moisture was studied with 16-day old pea and 21-day old lettuce plants respectively. Pea height and fresh biomass accumulation were not affected by transient substrate moisture increase. Net photosynthetic rate (Pn) of pea plants showed fast response to substrate moisture variation, while chlorophyll content did not change. Drastic change of substrate moisture suppressed lettuce Pn, chlorophyll biosynthesis and plant growth. These parameters slowly recovered after termination of waterlogging treatment but lettuce yield was greatly affected. The results showed that the most sensitive physiological parameter to substrate moisture variations is photosynthesis.

  9. Settlement determination of operating moisture of autoclaved aerated concrete in different climatic zones

    Directory of Open Access Journals (Sweden)

    Pastushkov Pavel Pavlovich

    Full Text Available In the process of operation of buildings the moisture state of enveloping structures materials is changing depending on their construction features, properties of the material, temperature and moisture conditions in the premises, climatic conditions of the construction area. Moisture mode determines the operational properties of the enveloping structures of a building. It directly influences the thermal characteristics of enveloping structure and energy efficiency of the applied materials. The analysis of the methods for calculation of moisture behavior of enclosing structures is carried out. The research relevance of operational moisture of AAC is substantiated. Experimental studies and results of the sorption moisturizing and water vapor permeability of leading marks of aerated concrete are carried out. The authors offer the results of numerical calculations of the moisture behavior of aerated concrete in the walls with mark D400 with facade thermal insulation composite systems - with external plaster layers for different climatic zones of construction.

  10. Impact of Soil Moisture Initialization on Seasonal Weather Prediction

    Science.gov (United States)

    Koster, Randal D.; Suarez, Max J.; Houser, Paul (Technical Monitor)

    2002-01-01

    The potential role of soil moisture initialization in seasonal forecasting is illustrated through ensembles of simulations with the NASA Seasonal-to-Interannual Prediction Project (NSIPP) model. For each boreal summer during 1997-2001, we generated two 16-member ensembles of 3-month simulations. The first, "AMIP-style" ensemble establishes the degree to which a perfect prediction of SSTs would contribute to the seasonal prediction of precipitation and temperature over continents. The second ensemble is identical to the first, except that the land surface is also initialized with "realistic" soil moisture contents through the continuous prior application (within GCM simulations leading up to the start of the forecast period) of a daily observational precipitation data set and the associated avoidance of model drift through the scaling of all surface prognostic variables. A comparison of the two ensembles shows that soil moisture initialization has a statistically significant impact on summertime precipitation and temperature over only a handful of continental regions. These regions agree, to first order, with regions that satisfy three conditions: (1) a tendency toward large initial soil moisture anomalies, (2) a strong sensitivity of evaporation to soil moisture, and (3) a strong sensitivity of precipitation to evaporation. The degree to which the initialization improves forecasts relative to observations is mixed, reflecting a critical need for the continued development of model parameterizations and data analysis strategies.

  11. Relationship between seed moisture content and acquisition of impermeability in Nelumbo nucifera (Nelumbonaceae

    Directory of Open Access Journals (Sweden)

    Ganesh K. Jaganathan

    Full Text Available ABSTRACT Seeds of Nelumbo nucifera do not imbibe water, and thus have physical dormancy (PY. However, a proportion of seeds are permeable to water, and so we hypothesized that variation in moisture content is a reason for the development of both permeable and impermeable seeds. The permeable proportion of seeds present in a lot collected from Suzhou, China, was separated using an imbibition test. The permeable proportion had an average moisture content of 15.6 %, compared with 8.5 % for impermeable seeds. Drying permeable seeds above silica gel to 10 % and 8 % f. wb., resulted in 77 and 100 % impermeable seeds, respectively, compared with no impermeable seeds at 15 % moisture content. Dried to 10 % moisture content, and incubated above water in an airtight container, 46 % of the seeds reverse impermeability. Permeable seeds with 15 % moisture content maintained above LiCl2 (RH=70 % did not develop impermeability after three months of storage. The seeds dried to 6 % moisture content and stored above water in an airtight container showed no increase in moisture. Based on these results, we conclude that there is a strong relationship between moisture content and the onset of impermeability in this species.

  12. SOIL moisture data intercomparison

    Science.gov (United States)

    Kerr, Yann; Rodriguez-Frenandez, Nemesio; Al-Yaari, Amen; Parens, Marie; Molero, Beatriz; Mahmoodi, Ali; Mialon, Arnaud; Richaume, Philippe; Bindlish, Rajat; Mecklenburg, Susanne; Wigneron, Jean-Pierre

    2016-04-01

    The Soil Moisture and Ocean Salinity satellite (SMOS) was launched in November 2009 and started delivering data in January 2010. Subsequently, the satellite has been in operation for over 6 years while the retrieval algorithms from Level 1 to Level 2 underwent significant evolutions as knowledge improved. Other approaches for retrieval at Level 2 over land were also investigated while Level 3 and 4 were initiated. In this présentation these improvements are assessed by inter-comparisons of the current Level 2 (V620) against the previous version (V551) and new products either using neural networks or Level 3. In addition a global evaluation of different SMOS soil moisture (SM) products is performed comparing products with those of model simulations and other satellites (AMSR E/ AMSR2 and ASCAT). Finally, all products were evaluated against in situ measurements of soil moisture (SM). The study demonstrated that the V620 shows a significant improvement (including those at level1 improving level2)) with respect to the earlier version V551. Results also show that neural network based approaches can yield excellent results over areas where other products are poor. Finally, global comparison indicates that SMOS behaves very well when compared to other sensors/approaches and gives consistent results over all surfaces from very dry (African Sahel, Arizona), to wet (tropical rain forests). RFI (Radio Frequency Interference) is still an issue even though detection has been greatly improved while RFI sources in several areas of the world are significantly reduced. When compared to other satellite products, the analysis shows that SMOS achieves its expected goals and is globally consistent over different eco climate regions from low to high latitudes and throughout the seasons.

  13. Enhanced Soil Moisture Initialization Using Blended Soil Moisture Product and Regional Optimization of LSM-RTM Coupled Land Data Assimilation System.

    Science.gov (United States)

    Nair, A. S.; Indu, J.

    2017-12-01

    Prediction of soil moisture dynamics is high priority research challenge because of the complex land-atmosphere interaction processes. Soil moisture (SM) plays a decisive role in governing water and energy balance of the terrestrial system. An accurate SM estimate is imperative for hydrological and weather prediction models. Though SM estimates are available from microwave remote sensing and land surface model (LSM) simulations, it is affected by uncertainties from several sources during estimation. Past studies have generally focused on land data assimilation (DA) for improving LSM predictions by assimilating soil moisture from single satellite sensor. This approach is limited by the large time gap between two consequent soil moisture observations due to satellite repeat cycle of more than three days at the equator. To overcome this, in the present study, we have performed DA using ensemble products from the soil moisture operational product system (SMOPS) blended soil moisture retrievals from different satellite sensors into Noah LSM. Before the assimilation period, the Noah LSM is initialized by cycling through seven multiple loops from 2008 to 2010 forcing with Global data assimilation system (GDAS) data over the Indian subcontinent. We assimilated SMOPS into Noah LSM for a period of two years from 2010 to 2011 using Ensemble Kalman Filter within NASA's land information system (LIS) framework. Results show that DA has improved Noah LSM prediction with a high correlation of 0.96 and low root mean square difference of 0.0303 m3/m3 (figure 1a). Further, this study has also investigated the notion of assimilating microwave brightness temperature (Tb) as a proxy for SM estimates owing to the close proximity of Tb and SM. Preliminary sensitivity analysis show a strong need for regional parameterization of radiative transfer models (RTMs) to improve Tb simulation. Towards this goal, we have optimized the forward RTM using swarm optimization technique for direct Tb

  14. Relationship of the moisture content of Finnish wheat flour and relative humidity

    Directory of Open Access Journals (Sweden)

    Yu-Yen Linko

    1968-01-01

    Full Text Available Changes in the moisture content of Finnish commercial wheat flour stored at variable relative humidities, representing the conditions typical of flour storage in Finland, were investigated. It could be shown that flour of 15 % moisture at the time of packing tends to dry considerably during normal storage conditions. Owing to the hysteresis effect, the moisture content of once dried flour is not likely to reach detrimental levels during normal storage, even if the relative humidity would exceed the critical level of 75—80 % for short periods. Minimum warehouse relative humidity was observed during Januay, at which time flour moisture had decreased to 6.7 %. The equilibrium humidity for flour of 15 % original moisture content was found to be about 70 %.

  15. Temperature and moisture content effects on compressive strength parallel to the grain of paricá

    Directory of Open Access Journals (Sweden)

    Manuel Jesús Manríquez Figueroa

    Full Text Available The aim of this study is to evaluate the effect of the temperature and moisture content on the compressive strength parallel to the grain of paricá (Schizolobium amazonicum Huber ex. Ducke from cultivated forests. The experiments were carried out on 3 timber samples under different conditions: heated (HT, thermal treatment (TT and water saturated (WS. The HT sample consisted of 105 clear specimens assembled in 15 groups, the TT consisted of 90 clear specimens assembled in 15 groups and the WS consisted of 90 clear specimens assembled in 9 groups. The specimens from HT and WS samples were tested at a temperature range from 20 to 230 ºC and 20 to 100 ºC, respectively. The HT specimens were tested at ambient temperature, but after being submitted to thermal treatment. The HT, TT and WS samples present a decrease in the compressive strength, reaching 65%, 76% and 59% of the compressive strength at room temperature, respectively. The decrease in the compressive strength of the HT and WS samples can be associated to the thermal degradation of wood polymers and the moisture content. For the TT sample, the strength increased for a pre-heating temperature of up to 170 °C due to the reduction in the moisture content of the specimens.

  16. The impact of fog on soil moisture dynamics in the Namib Desert

    Science.gov (United States)

    Li, Bonan; Wang, Lixin; Kaseke, Kudzai F.; Vogt, Roland; Li, Lin; Seely, Mary K.

    2018-03-01

    Soil moisture is a crucial component supporting vegetation dynamics in drylands. Despite increasing attention on fog in dryland ecosystems, the statistical characterization of fog distribution and how fog affects soil moisture dynamics have not been seen in literature. To this end, daily fog records over two years (Dec 1, 2014-Nov 1, 2016) from three sites within the Namib Desert were used to characterize fog distribution. Two sites were located within the Gobabeb Research and Training Center vicinity, the gravel plains and the sand dunes. The third site was located at the gravel plains, Kleinberg. A subset of the fog data during rainless period was used to investigate the effect of fog on soil moisture. A stochastic modeling framework was used to simulate the effect of fog on soil moisture dynamics. Our results showed that fog distribution can be characterized by a Poisson process with two parameters (arrival rate λ and average depth α (mm)). Fog and soil moisture observations from eighty (Aug 19, 2015-Nov 6, 2015) rainless days indicated a moderate positive relationship between soil moisture and fog in the Gobabeb gravel plains, a weaker relationship in the Gobabeb sand dunes while no relationship was observed at the Kleinberg site. The modeling results suggested that mean and major peaks of soil moisture dynamics can be captured by the fog modeling. Our field observations demonstrated the effects of fog on soil moisture dynamics during rainless periods at some locations, which has important implications on soil biogeochemical processes. The statistical characterization and modeling of fog distribution are of great value to predict fog distribution and investigate the effects of potential changes in fog distribution on soil moisture dynamics.

  17. Hysteresis of soil temperature under different soil moisture and ...

    African Journals Online (AJOL)

    ... in a solar greenhouse. The objective of this study was to find a simple method to estimate the hysteresis of soil temperature under three soil moisture and two fertilizer levels in solar greenhouse conditions with tomato crop (Lycopersicon esculentum Mill). The results show that the soil moisture had no significant effects on ...

  18. Applications of moisture monitoring using TAUPE-sensors

    International Nuclear Information System (INIS)

    Koeniger, F.

    2007-01-01

    TAUPE as a moisture sensor has been developed in cooperation with Technology Transfer Division in Forschungszentrum Karlsruhe since 1996. These sensors can be used to monitor moisture in a variety of materials, using time domain or frequency domain techniques. Major applications are large area supervision of landfill sealings, determination of the snow water equivalent, e.g. in the project SNOWPOWER for the forecasting of the amount of water for energy production in storage lakes and, as a new project, continuous monitoring of groundwater level in the flood plane of river Rhine. (orig.)

  19. Stochastic Models for the Kinematics of Moisture Transport and Condensation in Homogeneous Turbulent Flows

    OpenAIRE

    O'Gorman, Paul A.; Schneider, Tapio

    2006-01-01

    The transport of a condensing passive scalar is studied as a prototype model for the kinematics of moisture transport on isentropic surfaces. Condensation occurs whenever the scalar concentration exceeds a specified local saturation value. Since condensation rates are strongly nonlinear functions of moisture content, the mean moisture flux is generally not diffusive. To relate the mean moisture content, mean condensation rate, and mean moisture flux to statistics of the advecting velocity fie...

  20. Continuous data assimilation for downscaling large-footprint soil moisture retrievals

    KAUST Repository

    Altaf, Muhammad

    2016-01-01

    Soil moisture is a key component of the hydrologic cycle, influencing processes leading to runoff generation, infiltration and groundwater recharge, evaporation and transpiration. Generally, the measurement scale for soil moisture is found to be different from the modeling scales for these processes. Reducing this mismatch between observation and model scales in necessary for improved hydrological modeling. An innovative approach to downscaling coarse resolution soil moisture data by combining continuous data assimilation and physically based modeling is presented. In this approach, we exploit the features of Continuous Data Assimilation (CDA) which was initially designed for general dissipative dynamical systems and later tested numerically on the incompressible Navier-Stokes equation, and the Benard equation. A nudging term, estimated as the misfit between interpolants of the assimilated coarse grid measurements and the fine grid model solution, is added to the model equations to constrain the model\\'s large scale variability by available measurements. Soil moisture fields generated at a fine resolution by a physically-based vadose zone model (HYDRUS) are subjected to data assimilation conditioned upon coarse resolution observations. This enables nudging of the model outputs towards values that honor the coarse resolution dynamics while still being generated at the fine scale. Results show that the approach is feasible to generate fine scale soil moisture fields across large extents, based on coarse scale observations. Application of this approach is likely in generating fine and intermediate resolution soil moisture fields conditioned on the radiometerbased, coarse resolution products from remote sensing satellites.

  1. Monitoring Moisture Damage Propagation in GFRP Composites Using Carbon Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Sabagh

    2017-03-01

    Full Text Available Glass fiber reinforced polymer (GFRP composites are widely used in infrastructure applications including water structures due to their relatively high durability, high strength to weight ratio, and non-corrosiveness. Here we demonstrate the potential use of carbon nanoparticles dispersed during GFRP composite fabrication to reduce water absorption of GFRP and to enable monitoring of moisture damage propagation in GFRP composites. GFRP coupons incorporating 2.0 wt % carbon nanofibers (CNFs and 2.0 wt % multi-wall carbon nanotubes (MWCNTs were fabricated in order to study the effect of moisture damage on mechanical properties of GFRP. Water absorption tests were carried out by immersing the GFRP coupons in a seawater bath at two temperatures for a time period of three months. Effects of water immersion on the mechanical properties and glass transition temperature of GFRP were investigated. Furthermore, moisture damage in GFRP was monitored by measuring the electrical conductivity of the GFRP coupons. It was shown that carbon nanoparticles can provide a means of self-sensing that enables the monitoring of moisture damage in GFRP. Despite the success of the proposed technique, it might not be able to efficiently describe moisture damage propagation in GFRP beyond a specific threshold because of the relatively high electrical conductivity of seawater. Microstructural investigations using Fourier Transform Infrared (FTIR explained the significance of seawater immersion time and temperature on the different levels of moisture damage in GFRP.

  2. Remote Sensing of Surface Soil Moisture using Semi-Concurrent Radar and Radiometer Observations

    Science.gov (United States)

    Li, L.; Ouellette, J. D.; Colliander, A.; Cosh, M. H.; Caldwell, T. G.; Walker, J. P.

    2017-12-01

    Radar backscatter and radiometer brightness temperature both have well-documented sensitivity to surface soil moisture, particularly in the microwave regime. While radiometer-derived soil moisture retrievals have been shown to be stable and accurate, they are only available at coarse spatial resolutions on the order of tens of kilometers. Backscatter from Synthetic Aperture Radar (SAR) is similarly sensitive to soil moisture but can yield higher spatial resolutions, with pixel sizes about an order of magnitude smaller. Soil moisture retrieval from radar backscatter is more difficult, however, due to the combined sensitivity of radar scattering to surface roughness, vegetation structure, and soil moisture. The algorithm uses a time-series of SAR data to retrieval soil moisture information, constraining the SAR-derived soil moisture estimates with radiometer observations. This effectively combines the high spatial resolution offered by SAR with the precision offered by passive radiometry. The algorithm is a change detection approach which maps changes in the radar backscatter to changes in surface soil moisture. This new algorithm differs from existing retrieval techniques in that it does not require ancillary vegetation information, but assumes vegetation and surface roughness are stable between pairs of consecutive radar overpasses. Furthermore, this method does not require a radar scattering model for the vegetation canopy, nor the use of a training data set. The algorithm works over a long time series, and is constrained by hard bounds which are defined using a coarse-resolution radiometer soil moisture product. The presentation will include soil moisture retrievals from Soil Moisture Active/Passive (SMAP) SAR data. Two sets of optimization bounds will constrain the radar change detection algorithm: one defined by SMAP radiometer retrievals and one defined by WindSat radiometer retrievals. Retrieved soil moisture values will be presented on a world map and will

  3. The effect of combining a relative-humidity-sensitive ventilation system with the moisture-buffering capacity of materials on indoor climate and energy efficiency of buildings

    Energy Technology Data Exchange (ETDEWEB)

    Woloszyn, Monika [Universite de Lyon, Lyon F-69003 (France); Universite Lyon1, Villeurbanne F-69622 (France); INSA-Lyon, CETHIL UMR CNRS 5008, bat. Sadi Carnot, F-69621 Villeurbanne cedex (France); Kalamees, Targo [Chair of Building Physics and Architecture, Tallinn University of Technology, Ehiteja tee 5 19086 (Estonia); Olivier Abadie, Marc [Pontifical Catholic University of Parana - PUCPR/CCET-Thermal Systems Laboratory, Rua Imaculada Conceicao, 1155 Curitiba, PR 80215-901 (Brazil); LEPTIAB-University of La Rochelle, Avenue M. Crepeau, 17000 La Rochelle (France); Steeman, Marijke [Department of Architecture and Urban Planning, UGENT-Ghent University, J. Plateaustraat 22, 9000 Ghent (Belgium); Sasic Kalagasidis, Angela [Department of Building Technology, Chalmers University of Technology, Sven Hultins gata 8, 412 96 Gothenburg (Sweden)

    2009-03-15

    Indoor moisture management, which means keeping the indoor relative humidity (RH) at correct levels, is very important for whole building performance in terms of indoor air quality (IAQ), energy performance and durability of the building. In this study, the effect of combining a relative-humidity-sensitive (RHS) ventilation system with indoor moisture buffering materials was investigated. Four comprehensive heat-air-moisture (HAM) simulation tools were used to analyse the performance of different moisture management strategies in terms of IAQ and of energy efficiency. Despite some differences in results, a good agreement was found and similar trends were detected from the results, using the four different simulation tools. The results from simulations demonstrate that RHS ventilation reduces the spread between the minimum and maximum values of the RH in the indoor air and generates energy savings. Energy savings are achieved while keeping the RH at target level, not allowing for possible risk of condensations. The disadvantage of this type of demand controlled-ventilation is that other pollutants (such as CO{sub 2}) may exceed target values. This study also confirmed that the use of moisture-buffering materials is a very efficient way to reduce the amplitude of daily moisture variations. It was possible, by the combined effect of ventilation and wood as buffering material, to keep the indoor RH at a very stable level. (author)

  4. Downscaling Coarse Scale Microwave Soil Moisture Product using Machine Learning

    Science.gov (United States)

    Abbaszadeh, P.; Moradkhani, H.; Yan, H.

    2016-12-01

    Soil moisture (SM) is a key variable in partitioning and examining the global water-energy cycle, agricultural planning, and water resource management. It is also strongly coupled with climate change, playing an important role in weather forecasting and drought monitoring and prediction, flood modeling and irrigation management. Although satellite retrievals can provide an unprecedented information of soil moisture at a global-scale, the products might be inadequate for basin scale study or regional assessment. To improve the spatial resolution of SM, this work presents a novel approach based on Machine Learning (ML) technique that allows for downscaling of the satellite soil moisture to fine resolution. For this purpose, the SMAP L-band radiometer SM products were used and conditioned on the Variable Infiltration Capacity (VIC) model prediction to describe the relationship between the coarse and fine scale soil moisture data. The proposed downscaling approach was applied to a western US basin and the products were compared against the available SM data from in-situ gauge stations. The obtained results indicated a great potential of the machine learning technique to derive the fine resolution soil moisture information that is currently used for land data assimilation applications.

  5. Improving terrestrial evaporation estimates over continental Australia through assimilation of SMOS soil moisture

    Science.gov (United States)

    Martens, B.; Miralles, D.; Lievens, H.; Fernández-Prieto, D.; Verhoest, N. E. C.

    2016-06-01

    Terrestrial evaporation is an essential variable in the climate system that links the water, energy and carbon cycles over land. Despite this crucial importance, it remains one of the most uncertain components of the hydrological cycle, mainly due to known difficulties to model the constraints imposed by land water availability on terrestrial evaporation. The main objective of this study is to assimilate satellite soil moisture observations from the Soil Moisture and Ocean Salinity (SMOS) mission into an existing evaporation model. Our over-arching goal is to find an optimal use of satellite soil moisture that can help to improve our understanding of evaporation at continental scales. To this end, the Global Land Evaporation Amsterdam Model (GLEAM) is used to simulate evaporation fields over continental Australia for the period September 2010-December 2013. SMOS soil moisture observations are assimilated using a Newtonian Nudging algorithm in a series of experiments. Model estimates of surface soil moisture and evaporation are validated against soil moisture probe and eddy-covariance measurements, respectively. Finally, an analogous experiment in which Advanced Microwave Scanning Radiometer (AMSR-E) soil moisture is assimilated (instead of SMOS) allows to perform a relative assessment of the quality of both satellite soil moisture products. Results indicate that the modelled soil moisture from GLEAM can be improved through the assimilation of SMOS soil moisture: the average correlation coefficient between in situ measurements and the modelled soil moisture over the complete sample of stations increased from 0.68 to 0.71 and a statistical significant increase in the correlations is achieved for 17 out of the 25 individual stations. Our results also suggest a higher accuracy of the ascending SMOS data compared to the descending data, and overall higher quality of SMOS compared to AMSR-E retrievals over Australia. On the other hand, the effect of soil moisture data

  6. Predictability of soil moisture and streamflow on subseasonal timescales: A case study

    Science.gov (United States)

    Orth, Rene; Seneviratne, Sonia I.

    2013-10-01

    Hydrological forecasts constitute an important tool in water resource management, especially in the case of impending extreme events. This study investigates the potential predictability of soil moisture and streamflow in Switzerland using a conceptual model including a simple water balance representation and a snow module. Our results show that simulated soil moisture and streamflow are more predictable (as indicated by significantly improved performance compared to climatology) until lead times of approximately 1 week and 2-3 days, respectively, when using initial soil moisture information and climatological atmospheric forcing. Using also initial snow information and seasonal weather forecasts as forcing, the predictable lead time doubles in case of soil moisture and triples for streamflow. The skill contributions of the additional information vary with altitude; at low altitudes the precipitation forecast is most important, whereas in mountainous areas the temperature forecast and the initial snow information are the most valuable contributors. We find furthermore that the soil moisture and streamflow forecast skills increase with increasing initial soil moisture anomalies. Comparing the respective value of realistic initial conditions and state-of-the-art forcing forecasts, we show that the former are generally more important for soil moisture forecasts, whereas the latter are more valuable for streamflow forecasts. To relate the derived predictabilities to respective soil moisture and streamflow memories investigated in other publications, we additionally illustrate the similarity between the concepts of memory and predictability as measures of persistence in the last part of this study.

  7. Hydrologic responses to restored wildfire regimes revealed by soil moisture-vegetation relationships

    Science.gov (United States)

    Boisramé, Gabrielle; Thompson, Sally; Stephens, Scott

    2018-02-01

    Many forested mountain watersheds worldwide evolved with frequent fire, which Twentieth Century fire suppression activities eliminated, resulting in unnaturally dense forests with high water demand. Restoration of pre-suppression forest composition and structure through a variety of management activities could improve forest resilience and water yields. This study explores the potential for "managed wildfire", whereby naturally ignited fires are allowed to burn, to alter the water balance. Interest in this type of managed wildfire is increasing, yet its long-term effects on water balance are uncertain. We use soil moisture as a spatially-distributed hydrologic indicator to assess the influence of vegetation, fire history and landscape position on water availability in the Illilouette Creek Basin in Yosemite National Park. Over 6000 manual surface soil moisture measurements were made over a period of three years, and supplemented with continuous soil moisture measurements over the top 1m of soil in three sites. Random forest and linear mixed effects models showed a dominant effect of vegetation type and history of vegetation change on measured soil moisture. Contemporary and historical vegetation maps were used to upscale the soil moisture observations to the basin and infer soil moisture under fire-suppressed conditions. Little change in basin-averaged soil moisture was inferred due to managed wildfire, but the results indicated that large localized increases in soil moisture had occurred, which could have important impacts on local ecology or downstream flows.

  8. Ecosystem-scale plant hydraulic strategies inferred from remotely-sensed soil moisture

    Science.gov (United States)

    Bassiouni, M.; Good, S. P.; Higgins, C. W.

    2017-12-01

    Characterizing plant hydraulic strategies at the ecosystem scale is important to improve estimates of evapotranspiration and to understand ecosystem productivity and resilience. However, quantifying plant hydraulic traits beyond the species level is a challenge. The probability density function of soil moisture observations provides key information about the soil moisture states at which evapotranspiration is reduced by water stress. Here, an inverse Bayesian approach is applied to a standard bucket model of soil column hydrology forced with stochastic precipitation inputs. Through this approach, we are able to determine the soil moisture thresholds at which stomata are open or closed that are most consistent with observed soil moisture probability density functions. This research utilizes remotely-sensed soil moisture data to explore global patterns of ecosystem-scale plant hydraulic strategies. Results are complementary to literature values of measured hydraulic traits of various species in different climates and previous estimates of ecosystem-scale plant isohydricity. The presented approach provides a novel relation between plant physiological behavior and soil-water dynamics.

  9. [Simulation of cropland soil moisture based on an ensemble Kalman filter].

    Science.gov (United States)

    Liu, Zhao; Zhou, Yan-Lian; Ju, Wei-Min; Gao, Ping

    2011-11-01

    By using an ensemble Kalman filter (EnKF) to assimilate the observed soil moisture data, the modified boreal ecosystem productivity simulator (BEPS) model was adopted to simulate the dynamics of soil moisture in winter wheat root zones at Xuzhou Agro-meteorological Station, Jiangsu Province of China during the growth seasons in 2000-2004. After the assimilation of observed data, the determination coefficient, root mean square error, and average absolute error of simulated soil moisture were in the ranges of 0.626-0.943, 0.018-0.042, and 0.021-0.041, respectively, with the simulation precision improved significantly, as compared with that before assimilation, indicating the applicability of data assimilation in improving the simulation of soil moisture. The experimental results at single point showed that the errors in the forcing data and observations and the frequency and soil depth of the assimilation of observed data all had obvious effects on the simulated soil moisture.

  10. Comparison of Soil Moisture in Switzerland Using In-Situ Measurements and Model Output

    Science.gov (United States)

    Mittelbach, H.; Orth, R.; Seneviratne, S. I.

    2011-01-01

    Soil moisture is an essential contributor to land surface- atmosphere interactions. In this study we evaluate the two Land surface models CLM3.5 and SIB3 regarding their performance in simulating soil moisture and its anomalies for the one year period 01.09.2009 to 31.08.2010. Four grassland sites from the SwissSMEX/- Veg project were used as reference soil moisture data. In general, both models represent the soil moisture anomalies and their distribution better than the absolute soil moisture. Furthermore, both models show a seasonal dependence of the correlation and root mean square error. In contrast to the SIB3 model, the CLM3.5 model shows stronger seasonal variation of the root mean square error and a larger interquantile range for soil moisture anomalies.

  11. The error analysis of coke moisture measured by neutron moisture gauge

    International Nuclear Information System (INIS)

    Tian Huixing

    1995-01-01

    The error of coke moisture measured by neutron method in the iron and steel industry is analyzed. The errors are caused by inaccurate sampling location in the calibration procedure on site. By comparison, the instrument error and the statistical fluctuation error are smaller. So the sampling proportion should be increased as large as possible in the calibration procedure on site, and a satisfied calibration effect can be obtained on a suitable size hopper

  12. Moisture buffering and its consequence in whole building hygrothermal modeling

    DEFF Research Database (Denmark)

    Rode, Carsten; Grau, Karl

    2008-01-01

    Moisture absorption and desorption of materials in contact with indoor air of buildings can be used as a passive, i.e., nonmechanical, way to moderate the variation of indoor humidity. This phenomenon, which is recognized as,moisture buffering', could potentially be used as an attractive feature...... for ventilation if indoor humidity is a parameter for controlling ventilation rate, 2. it is possible to improve the perceived acceptability of indoor air, as judged by the temperature and humidity of the air, by using moisture buffering to control the indoor humidity. The results of the whole building...

  13. Short Communications Sand moisture as a factor determining depth ...

    African Journals Online (AJOL)

    1993-11-05

    Nov 5, 1993 ... The depths to which the animals burrow are, at least partly. determined by the moisture gradient in the sand. They are, however, incapable of burrowing into totally dry sand. Animals alter their position in the sand in response to changes in moisture content so as to ensure exposure to suitable conditions.

  14. The influence of ventilation on moisture conditions in facades with wooden cladding

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Brandt, Erik

    2009-01-01

    A ventilated cavity behind the cladding of timber frame walls is often considered good building practice that facilitates the removal of moisture from the construction. However, moisture will only be removed from the construction by ventilating it with dry air, whereas ventilating with humid air...... might add moisture to the construction. Full-size wall elements with wooden cladding placed in a test building were exposed to natural climate on the outside and to a humid indoor climate on the inside. Temperature and moisture conditions inside the wall elements and climate parameters were monitored...

  15. Calibration of moisture monitors

    International Nuclear Information System (INIS)

    Gutierrez, R.L.

    1979-02-01

    A method for calibrating an aluminum oxide hygrometer against an optical chilled mirror dew-point hygrometer has been established. A theoretical cross-point line of dew points from both hygrometers and a maximum moisture content of 10 ppM/sub v/ are used to define an area for calibrating the sensor probes of the aluminum oxide hygrometer

  16. Moisture-driven xylogenesis in Pinus ponderosa from a Mojave Desert mountain reveals high phenological plasticity.

    Science.gov (United States)

    Ziaco, Emanuele; Truettner, Charles; Biondi, Franco; Bullock, Sarah

    2018-04-01

    Future seasonal dynamics of wood formation in hyperarid environments are still unclear. Although temperature-driven extension of the growing season and increased forest productivity are expected for boreal and temperate biomes under global warming, a similar trend remains questionable in water-limited regions. We monitored cambial activity in a montane stand of ponderosa pine (Pinus ponderosa) from the Mojave Desert for 2 consecutive years (2015-2016) showing opposite-sign anomalies between warm- and cold-season precipitation. After the wet winter/spring of 2016, xylogenesis started 2 months earlier compared to 2015, characterized by abundant monsoonal (July-August) rainfall and hyperarid spring. Tree size did not influence the onset and ending of wood formation, highlighting a predominant climatic control over xylem phenological processes. Moisture conditions in the previous month, in particular soil water content and dew point, were the main drivers of cambial phenology. Latewood formation started roughly at the same time in both years; however, monsoonal precipitation triggered the formation of more false rings and density fluctuations in 2015. Because of uncertainties in future precipitation patterns simulated by global change models for the Southwestern United States, the dependency of P. ponderosa on seasonal moisture implies a greater conservation challenge than for species that respond mostly to temperature conditions. © 2018 John Wiley & Sons Ltd.

  17. Soil moisture transport during the 1974--1975 and 1975--1976 water years

    International Nuclear Information System (INIS)

    Last, G.V.; Easley, P.G.; Brown, D.J.

    1976-12-01

    The rate and direction of soil moisture movement in Hanford sediments were determined for the 1974-1975 and 1975-1976 water years. The data for these determinations was obtained from two large lysimeters located on the 200 area plateau near the center of the Hanford Reservation. During the 1974-75 water year, meteoric moisture percolated to a depth of 2.5 meters with a peak moisture content of 10.5 volume-percent. This percolation envelope was eliminated by evaporation during the hot dry summer of 1975. The 1975-76 water year had only 70 percent of the normal precipitation, thus the percolation envelope was small and penetrated to a depth of only two meters. However, in spite of this shallow depth and low volume of moisture, the percolation envelope was not eliminated by the end of the water year because of lower seasonal temperatures and higher humidity during the drying season. Moisture content of sediments in the 4-18 meter depth range showed no relative change throughout the two water years, and no moisture accumulated at the bottom of the lysimeters, which indicates there is no deep percolation of meteoric moisture at this site, and no recharge to the ground water

  18. Moisture diffusion coefficients determination of furan bonded sands and water based foundry coatings

    DEFF Research Database (Denmark)

    Di Muoio, Giovanni Luca; Tiedje, Niels Skat

    2016-01-01

    Moisture content in furan bonded sand and water based coatings can be one of the main causes for gas related defects in large cast iron parts. Moisture diffusion coefficients for these materials are needed to precisely predict the possible moisture levels in foundry moulds. In this study, we first...... provide an example on how it is possible to apply this knowledge to estimate moisture variation in a sand mould during production....

  19. Radiographic testing of wood

    International Nuclear Information System (INIS)

    Osterloh, K.; Zscherpel, U.; Raedel, C.; Weidemann, G.; Meinel, D.; Goebbels, J.; Ewert, U.; Hasenstab, A.; Buecherl, T.

    2007-01-01

    Wood is an old and established consumption and construction material. It is still the most common material for constructing furniture, roofs, playgrounds and mine supports. In contrast to steel and concrete, wood warns of extreme loads by creaking. Its mechanical stability is more influenced by decay than by peripheral cracks. While external cracks are visible, internal decay by fungus growth is undetectable from outside. This may be a safety problem in supporting structures. The best analysis of the internal structure is provided by computed tomography, but this is also the most complex method, much more so than simple radiographic testing. However, the latter is made inaccurate by scattered radiation resulting from internal moisture. With the image processing options of digital radiographic techniques, the structural information can be separated effectively from noise. In contrast to X-ray and gamma radiography, neutron radiography provides information on the spatial distribution of moisture. In healthy wood, water is conducted in the sapwood while the hardwood is dry. Moisture in hardwood is caused by infestations, e.g. fungus growth. The contribution presents a comparative analysis of the available radiographic methods. (orig.)

  20. Indoor microbiota in severely moisture damaged homes and the impact of interventions.

    Science.gov (United States)

    Jayaprakash, Balamuralikrishna; Adams, Rachel I; Kirjavainen, Pirkka; Karvonen, Anne; Vepsäläinen, Asko; Valkonen, Maria; Järvi, Kati; Sulyok, Michael; Pekkanen, Juha; Hyvärinen, Anne; Täubel, Martin

    2017-10-13

    The limited understanding of microbial characteristics in moisture-damaged buildings impedes efforts to clarify which adverse health effects in the occupants are associated with the damage and to develop effective building intervention strategies. The objectives of this current study were (i) to characterize fungal and bacterial microbiota in house dust of severely moisture-damaged residences, (ii) to identify microbial taxa associated with moisture damage renovations, and (iii) to test whether the associations between the identified taxa and moisture damage are replicable in another cohort of homes. We applied bacterial 16S rRNA gene and fungal ITS amplicon sequencing complemented with quantitative PCR and chemical-analytical approaches to samples of house dust, and also performed traditional cultivation of bacteria and fungi from building material samples. Active microbial growth on building materials had significant though small influence on the house dust bacterial and fungal communities. Moisture damage interventions-including actual renovation of damaged homes and cases where families moved to another home-had only a subtle effect on bacterial community structure, seen as shifts in abundance weighted bacterial profiles after intervention. While bacterial and fungal species richness were reduced in homes that were renovated, they were not reduced for families that moved houses. Using different discriminant analysis tools, we were able identify taxa that were significantly reduced in relative abundance during renovation of moisture damage. For bacteria, the majority of candidates belonged to different families within the Actinomycetales order. Results for fungi were overall less consistent. A replication study in approximately 400 homes highlighted some of the identified taxa, confirming associations with observations of moisture damage and mold. The present study is one of the first studies to analyze changes in microbiota due to moisture damage interventions

  1. Effect of Root Moisture Content and Diameter on Root Tensile Properties

    Science.gov (United States)

    Yang, Yuanjun; Chen, Lihua; Li, Ning; Zhang, Qiufen

    2016-01-01

    The stabilization of slopes by vegetation has been a topical issue for many years. Root mechanical characteristics significantly influence soil reinforcement; therefore it is necessary to research into the indicators of root tensile properties. In this study, we explored the influence of root moisture content on tensile resistance and strength with different root diameters and for different tree species. Betula platyphylla, Quercus mongolica, Pinus tabulaeformis, and Larix gmelinii, the most popular tree species used for slope stabilization in the rocky mountainous areas of northern China, were used in this study. A tensile test was conducted after root samples were grouped by diameter and moisture content. The results showedthat:1) root moisture content had a significant influence on tensile properties; 2) slightly loss of root moisture content could enhance tensile strength, but too much loss of water resulted in weaker capacity for root elongation, and consequently reduced tensile strength; 3) root diameter had a strong positive correlation with tensile resistance; and4) the roots of Betula platyphylla had the best tensile properties when both diameter and moisture content being controlled. These findings improve our understanding of root tensile properties with root size and moisture, and could be useful for slope stabilization using vegetation. PMID:27003872

  2. Upscaling of Surface Soil Moisture Using a Deep Learning Model with VIIRS RDR

    Directory of Open Access Journals (Sweden)

    Dongying Zhang

    2017-04-01

    Full Text Available In current upscaling of in situ surface soil moisture practices, commonly used novel statistical or machine learning-based regression models combined with remote sensing data show some advantages in accurately capturing the satellite footprint scale of specific local or regional surface soil moisture. However, the performance of most models is largely determined by the size of the training data and the limited generalization ability to accomplish correlation extraction in regression models, which are unsuitable for larger scale practices. In this paper, a deep learning model was proposed to estimate soil moisture on a national scale. The deep learning model has the advantage of representing nonlinearities and modeling complex relationships from large-scale data. To illustrate the deep learning model for soil moisture estimation, the croplands of China were selected as the study area, and four years of Visible Infrared Imaging Radiometer Suite (VIIRS raw data records (RDR were used as input parameters, then the models were trained and soil moisture estimates were obtained. Results demonstrate that the estimated models captured the complex relationship between the remote sensing variables and in situ surface soil moisture with an adjusted coefficient of determination of R ¯ 2 = 0.9875 and a root mean square error (RMSE of 0.0084 in China. These results were more accurate than the Soil Moisture Active Passive (SMAP active radar soil moisture products and the Global Land data assimilation system (GLDAS 0–10 cm depth soil moisture data. Our study suggests that deep learning model have potential for operational applications of upscaling in situ surface soil moisture data at the national scale.

  3. Inferring Soil Moisture Memory from Streamflow Observations Using a Simple Water Balance Model

    Science.gov (United States)

    Orth, Rene; Koster, Randal Dean; Seneviratne, Sonia I.

    2013-01-01

    Soil moisture is known for its integrative behavior and resulting memory characteristics. Soil moisture anomalies can persist for weeks or even months into the future, making initial soil moisture a potentially important contributor to skill in weather forecasting. A major difficulty when investigating soil moisture and its memory using observations is the sparse availability of long-term measurements and their limited spatial representativeness. In contrast, there is an abundance of long-term streamflow measurements for catchments of various sizes across the world. We investigate in this study whether such streamflow measurements can be used to infer and characterize soil moisture memory in respective catchments. Our approach uses a simple water balance model in which evapotranspiration and runoff ratios are expressed as simple functions of soil moisture; optimized functions for the model are determined using streamflow observations, and the optimized model in turn provides information on soil moisture memory on the catchment scale. The validity of the approach is demonstrated with data from three heavily monitored catchments. The approach is then applied to streamflow data in several small catchments across Switzerland to obtain a spatially distributed description of soil moisture memory and to show how memory varies, for example, with altitude and topography.

  4. Theoretical study of soil water balance and process of soil moisture evaporation

    Directory of Open Access Journals (Sweden)

    Yu. A. Savel'ev

    2017-01-01

    Full Text Available Nearly a half of all grain production in the Russian Federation is grown in dry regions. But crop production efficiency there depends on amount of moisture, available to plants. However deficit of soil moisture is caused not only by a lack of an atmospheric precipitation, but also inefficient water saving: losses reach 70 percent. With respect thereto it is important to reveal the factors influencing intensity of soil moisture evaporation and to develop methods of decrease in unproductive moisture losses due to evaporation. The authors researched soil water balance theoretically and determined the functional dependences of moisture loss on evaporation. Intensity of moisture evaporation depends on physicomechanical characteristics of the soil, a consistence of its surface and weather conditions. To decrease losses of moisture for evaporation it is necessary, first, to improve quality of crumbling of the soil and therefore to reduce the evaporating surface of the soil. Secondly - to create the protective mulching layer which will allow to enhance albedo of the soil and to reduce its temperature that together will reduce unproductive evaporative water losses and will increase its inflow in case of condensation from air vapors. The most widespread types of soil cultivation are considered: disk plowing and stubble mulch plowing. Agricultural background «no tillage» was chosen as a control. Subsoil mulching tillage has an essential advantage in a storage of soil moisture. So, storage of soil moisture after a disking and in control (without tillage decreased respectively by 24.9 and 19.8 mm while at the mulching tillage this indicator revised down by only 15.6 mm. The mulching layer has lower heat conductivity that provides decrease in unproductive evaporative water losses.

  5. Moisture monitoring of ferrocyanide tanks: An evaluation of methods and tools

    International Nuclear Information System (INIS)

    Meacham, J.E.; Babad, H.; Toffer, H.

    1993-04-01

    This report reviews the strengths and limitations of moisture monitoring technologies that could be used for determining moisture concentration in Hanford Site single-shell ferrocyanide waste tanks. Two technologies (neutron diffusion and near-infrared spectroscopy) are being pursued as part of the ferrocyanide program. A third technology, Raman spectroscopy, is in development as a speciation tool at the Westinghouse Hanford Company 222-S Laboratory. The potential application of Raman spectroscopy to moisture monitoring is discussed

  6. Moisture transport properties of mortar and mortar joint: A NMR study

    OpenAIRE

    Brocken, H.J.P.; Adant, O.C.G.; Pel, L.

    1997-01-01

    The moisture transport in mortar and mortar joint often is an important parameter in degeneration of brick masonry and other block constructions. In this study, the influence of single additives on the moisture transport properties of mortar is investigated. Due to water extraction during brick laying, curing conditions of mortar in mortar joint differ from curing conditions of separately cured mortar. Consequently, the moisture transport properties of mortar joint differ. In addition to the ...

  7. Moisture transport properties of mortar and mortar joint: a NMR study

    OpenAIRE

    Brocken, H.J.P.; Adan, O.C.G.; Pel, L.

    1997-01-01

    The moisture transport in mortar and mortar joint often is an important parameter in degeneration of brick masonry and other block constructions. In this study, the influence of single additives on the moisture transport properties of mortar is investigated. Due to water extraction during brick laying, curing conditions of mortar in mortar joint differ from curing conditions of separately cured mortar. Consequently, the moisture transport properties of mortar joint differ. In addition to the ...

  8. A New Approach in Downscaling Microwave Soil Moisture Product using Machine Learning

    Science.gov (United States)

    Abbaszadeh, Peyman; Yan, Hongxiang; Moradkhani, Hamid

    2016-04-01

    Understating the soil moisture pattern has significant impact on flood modeling, drought monitoring, and irrigation management. Although satellite retrievals can provide an unprecedented spatial and temporal resolution of soil moisture at a global-scale, their soil moisture products (with a spatial resolution of 25-50 km) are inadequate for regional study, where a resolution of 1-10 km is needed. In this study, a downscaling approach using Genetic Programming (GP), a specialized version of Genetic Algorithm (GA), is proposed to improve the spatial resolution of satellite soil moisture products. The GP approach was applied over a test watershed in United States using the coarse resolution satellite data (25 km) from Advanced Microwave Scanning Radiometer - EOS (AMSR-E) soil moisture products, the fine resolution data (1 km) from Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation index, and ground based data including land surface temperature, vegetation and other potential physical variables. The results indicated the great potential of this approach to derive the fine resolution soil moisture information applicable for data assimilation and other regional studies.

  9. Effect of moisture on the accuracy of coke-ash determination by X-ray backscattering

    International Nuclear Information System (INIS)

    Pandey, H.D.; Prasad, M.S.

    1984-01-01

    Effect of moisture on the rapid non-destructive estimation of ash content in coal specimens using the X-ray backscattering technique has been studied extensively by various workers. In the present work, an attempt has been made to estimate its influence when the technique is extended to coke-ash determinations. From the study of the variation of backscattered intensity with change in the moisture content of a coke specimen, it is observed that the ash content varies significantly at moisture levels higher than 5%. The variation, however, remains within allowable limits if the moisture level is kept below 5%. This observation is confirmed by the actual measurement of ash percentages in thirteen coke specimens containing three different states of moisture levels viz. (i) in the dry state, (ii) with 5% moisture and (iii) with 10% moisture. (author)

  10. The effect of soil moisture anomalies on maize yield in Germany

    Science.gov (United States)

    Peichl, Michael; Thober, Stephan; Meyer, Volker; Samaniego, Luis

    2018-03-01

    Crop models routinely use meteorological variations to estimate crop yield. Soil moisture, however, is the primary source of water for plant growth. The aim of this study is to investigate the intraseasonal predictability of soil moisture to estimate silage maize yield in Germany. We also evaluate how approaches considering soil moisture perform compare to those using only meteorological variables. Silage maize is one of the most widely cultivated crops in Germany because it is used as a main biomass supplier for energy production in the course of the German Energiewende (energy transition). Reduced form fixed effect panel models are employed to investigate the relationships in this study. These models are estimated for each month of the growing season to gain insights into the time-varying effects of soil moisture and meteorological variables. Temperature, precipitation, and potential evapotranspiration are used as meteorological variables. Soil moisture is transformed into anomalies which provide a measure for the interannual variation within each month. The main result of this study is that soil moisture anomalies have predictive skills which vary in magnitude and direction depending on the month. For instance, dry soil moisture anomalies in August and September reduce silage maize yield more than 10 %, other factors being equal. In contrast, dry anomalies in May increase crop yield up to 7 % because absolute soil water content is higher in May compared to August due to its seasonality. With respect to the meteorological terms, models using both temperature and precipitation have higher predictability than models using only one meteorological variable. Also, models employing only temperature exhibit elevated effects.

  11. Effects of moisture on the mechanical properties of glass fibre ...

    Indian Academy of Sciences (India)

    Unknown

    of moisture absorption and correlating with the mechanical properties, it was observed that the ..... where F is the flux of moisture molecules crossing a unit ... 300. 400. 500. 600. 700 wt% of nascent fibre loading. 63.50. 55.75. 48.48. 38.63.

  12. A model for moisture-induced dimensional instability in printing paper

    NARCIS (Netherlands)

    van der Sman, C.G.; Bosco, E.; Peerlings, R.H.J.

    2016-01-01

    The dimensional stability of printing paper is strongly related to changes in moisture content. This represents a major issue in the field of digital ink-jet printing, where moisture induced reversible and irreversible deformations may compromise printing quality and runnability. This paper proposes

  13. Non-destructive radio-frequency and microwave measurement of moisture content in agricultural commodities

    International Nuclear Information System (INIS)

    Nelson, S.O.

    1994-01-01

    The importance of moisture content in agricultural commodities, the usefulness of the dielectric properties of such products for sensing moisture content by radiofrequency and microwave measurements, and factors affecting these properties are briefly discussed. Recent developments in the understanding of principles for online moisture sensing and the sensing of individual kernel, seed, nut and fruit moisture contents by radiofrequency and microwave techniques are reviewed. A brief discussion is included on aspects of practical application

  14. Full scale tests of moisture buffer capacity of wall materials

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Rode, Carsten; Peuhkuri, Ruut Hannele

    2005-01-01

    that are harmful such as growth of house dust mites, surface condensation and mould growth. Therefore a series of experiments has been carried out in a full scale test facility to determine the moisture buffer effect of interior walls of cellular concrete and plaster board constructions. For the cellular concrete......Moisture buffer capacity of hygroscopic materials can be used to moderate peaks in the relative humidity (RH) of indoor air as well as moisture content variations in building materials and furnishing. This can help to ensure healthier indoor environments by preventing many processes...... of the changes of moisture content in specimens of the wall composites exposed to the same environment. It was found that the finishes had a big impact on the buffer performance of the underlying materials. Even though the untreated cellular concrete had a very high buffer capacity, the effect was strongly...

  15. Laboratory evaluation of resistance to moisture damage in asphalt mixtures

    Directory of Open Access Journals (Sweden)

    Ahmed Ebrahim Abu El-Maaty Behiry

    2013-09-01

    Full Text Available Moisture damage in asphalt mixtures refers to loss in strength and durability due to the presence of water. Egypt road network is showing severe deterioration such as raveling and stripping because the bond between aggregates and asphalt film is broken due to water intrusion. To minimize moisture damage, asphalt mixes are investigated to evaluate the effect of air voids, degree of saturation, media of attack and the conditioning period. Two medias of attack are considered and two anti-stripping additives are used (hydrated lime and Portland cement. The retained Marshall stability and tensile strength ratio are calculated to determine the resistance to moisture damage. The results showed that both lime and cement could increase Marshall stability, resilient modulus, tensile strength and resistance to moisture damage of mixtures especially at higher condition periods. Use of hydrated lime had better results than Portland cement.

  16. Water sorption in wood and modified wood at high values of relative humidity

    DEFF Research Database (Denmark)

    Engelund, Emil Tang; Thygesen, Lisbeth Garbrecht; Hoffmeyer, Preben

    2010-01-01

    A theoretical study of the amount of moisture held in wood as capillary condensed water in the relative humidity (RH) range of 90–99.9% is carried out. The study is based on idealized geometries of the softwood structure related to micrographs. It is confined to structural elements such as bordered......, and different degrees of pit aspiration are assigned to earlywood and latewood. We suggest based on the results that capillary condensation makes only a very small contribution to the equilibrium moisture content. At 99.9% RH the contribution amounts to less than 0.0035 kg water per kg dry wood. This is in line...

  17. WOOD PROPERTIES AND EFFECT OF WOOD PROPERTIES ON THE WOOD FINISHING

    Directory of Open Access Journals (Sweden)

    Abdulkadir Malkoçoğlu

    2006-04-01

    Full Text Available Wood is basic raw material for furniture and joinery industries with wood structures. Wood is a biological material that has widely different properties depending on species, geographic area where the tree grew, the growth condition, size of the tree at harvest, sawing, and other manufacturing processes. Wood properties have been characterized within two groups as natural and manufacturing factors that effects finishing performance. Grow rate, density, knots, moisture content, extractives and juvenile wood are natural characteristics. Grain orientation, texture, drying and performance expectations are manufacturing characteristics. In this review, the effects of natural and manufacturing characteristics are discussed on the surface finishing performance of wood.

  18. A comparison of two methods for estimating conifer live foliar moisture content

    Science.gov (United States)

    W. Matt Jolly; Ann M. Hadlow

    2012-01-01

    Foliar moisture content is an important factor regulating how wildland fires ignite in and spread through live fuels but moisture content determination methods are rarely standardised between studies. One such difference lies between the uses of rapid moisture analysers or drying ovens. Both of these methods are commonly used in live fuel research but they have never...

  19. Adjustments of microwave-based measurements on coal moisture using natural radioactivity techniques

    Energy Technology Data Exchange (ETDEWEB)

    Prieto-Fernandez, I.; Luengo-Garcia, J.C.; Alonso-Hidalgo, M.; Folgueras-Diaz, B. [University of Oviedo, Gijon (Spain)

    2006-01-07

    The use of nonconventional on-line measurements of moisture and ash content in coal is presented. The background research is briefly reviewed. The possibilities of adjusting microwave-based moisture measurements using natural radioactive techniques, and vice versa, are proposed. The results obtained from the simultaneous analysis of moisture and ash content as well as the correlation improvements are shown.

  20. Direct observations of rock moisture, a hidden component of the hydrologic cycle.

    Science.gov (United States)

    Rempe, Daniella M; Dietrich, William E

    2018-03-13

    Recent theory and field observations suggest that a systematically varying weathering zone, that can be tens of meters thick, commonly develops in the bedrock underlying hillslopes. Weathering turns otherwise poorly conductive bedrock into a dynamic water storage reservoir. Infiltrating precipitation typically will pass through unsaturated weathered bedrock before reaching groundwater and running off to streams. This invisible and difficult to access unsaturated zone is virtually unexplored compared with the surface soil mantle. We have proposed the term "rock moisture" to describe the exchangeable water stored in the unsaturated zone in weathered bedrock, purposely choosing a term parallel to, but distinct from, soil moisture, because weathered bedrock is a distinctly different material that is distributed across landscapes independently of soil thickness. Here, we report a multiyear intensive campaign of quantifying rock moisture across a hillslope underlain by a thick weathered bedrock zone using repeat neutron probe measurements in a suite of boreholes. Rock moisture storage accumulates in the wet season, reaches a characteristic upper value, and rapidly passes any additional rainfall downward to groundwater. Hence, rock moisture storage mediates the initiation and magnitude of recharge and runoff. In the dry season, rock moisture storage is gradually depleted by trees for transpiration, leading to a common lower value at the end of the dry season. Up to 27% of the annual rainfall is seasonally stored as rock moisture. Significant rock moisture storage is likely common, and yet it is missing from hydrologic and land-surface models used to predict regional and global climate.

  1. Development of nuclear density and moisture gauges

    International Nuclear Information System (INIS)

    Zhu Huaian; Zhu Dichen; Jiang Yulan; Yin Xiling; Li Jianwen; Cheng Jianbing; Yan Haiqing

    1993-01-01

    The model MT5012 nuclear density and moisture gauge is an advanced portable meter to inspect the compactness of a highway roadbed and pavement foundation. It has perfect functions and the advantage of quickness, accuracy and non-destruction. It is also applicable to civil engineering, such as railway, airport and embankment. The model MT5022 nuclear density and moisture gauge is a mobile meter for continuous inspection and control of the compactness of a highway and pavement foundation. It can be installed on road roller, wheelbarrow and other traffic machines while working, and is more efficient than the portable ones

  2. Photoprotection in moisturizers and daily-care products.

    Science.gov (United States)

    Seite, S; Fourtanier, A; Rougier, A

    2010-10-01

    During usual daily activities, an appropriate protection against solar UV exposure should prevent clinical, cellular and molecular changes potentially leading to photoaging. In skin areas regularly exposed to sun, UV-damage is superimposed to tissue degeneration resulting from chronological aging. It is, therefore, important to know if moisturizers and daily-care products containing UVA absorbers combined with UVB ones are able to prevent these skin damages. This review will summarize clinical studies evaluating this topic. These studies demonstrate that broad-spectrum protection in moisturizers or daily-care products can prevent the "silent" sub-erythemal cumulative effects of UVR from inadvertent sun exposure.

  3. Fiber Optic Thermo-Hygrometers for Soil Moisture Monitoring.

    Science.gov (United States)

    Leone, Marco; Principe, Sofia; Consales, Marco; Parente, Roberto; Laudati, Armando; Caliro, Stefano; Cutolo, Antonello; Cusano, Andrea

    2017-06-20

    This work deals with the fabrication, prototyping, and experimental validation of a fiber optic thermo-hygrometer-based soil moisture sensor, useful for rainfall-induced landslide prevention applications. In particular, we recently proposed a new generation of fiber Bragg grating (FBGs)-based soil moisture sensors for irrigation purposes. This device was realized by integrating, inside a customized aluminum protection package, a FBG thermo-hygrometer with a polymer micro-porous membrane. Here, we first verify the limitations, in terms of the volumetric water content (VWC) measuring range, of this first version of the soil moisture sensor for its exploitation in landslide prevention applications. Successively, we present the development, prototyping, and experimental validation of a novel, optimized version of a soil VWC sensor, still based on a FBG thermo-hygrometer, but able to reliably monitor, continuously and in real-time, VWC values up to 37% when buried in the soil.

  4. Runtime and Inversion Impacts on Estimation of Moisture Retention Relations by Centrifuge

    Science.gov (United States)

    Sigda, J. M.; Wilson, J. L.

    2003-12-01

    Standard laboratory methods in soil physics for measuring the moisture retention relation (drainage matric potential-volumetric moisture content relation) are each limited to only part of the moisture content range. Centrifuge systems allow intensive accurate measurements across much of the saturation range, and typically require much less time than traditional laboratory methods. An initially liquid-saturated sample is subjected to a stepwise-increasing series of angular velocities while carefully monitoring changes in liquid content. Angular velocity is held constant until the capillary and centrifugal forces equilibrate, forcing liquid flux to zero, and then a final average liquid content is noted. The procedure is repeated after increasing the angular velocity. Centrifuge measurement time is greatly reduced because the centrifugal body force gradient can far exceed the driving forces utilized in standard lab methods. Widely-used in the petroleum industry for decades, centrifuge measurement of moisture retention relations is seldom encountered in the soil physics or vadose hydrology literatures. Yet there is a need to better understand and improve the experimental methodology given the increasing number of centrifuges employed in these fields. Errors in centrifuge measurement of moisture retention relations originate from both experimental protocol and from data inversion. Like standard methods, centrifuge methods assume equilibrium conditions, and so are sensitive to errors introduced by insufficient runtimes. Unlike standard methods, centrifuge experiments require inversion of the angular velocity and average sample moisture content data to a location-specific pair of matric potential and moisture content values, The force balance causes matric potential and moisture content to vary with sample length while the sample is spinning. Numerous data inversion techniques exist, each yielding different moisture retention relations. We present analyses demonstrating

  5. Thermodynamic analysis on heavy metals partitioning impacted by moisture during the MSW incineration

    International Nuclear Information System (INIS)

    Zhang Yanguo; Li Qinghai; Jia Jinyan; Meng Aihong

    2012-01-01

    Highlights: ► Partitioning of HMs affected by moisture was investigated by thermodynamic analysis. ► Increase in moisture and in temperature was opposite impact on HMs contribution. ► The extent of temperature decreased by increase in moisture determines the impact. - Abstract: A thermodynamic calculation was carried out to predict the behavior and speciation of heavy metals (HMs), Pb, Zn, Cu, and Cd, during municipal solid waste (MSW) incineration with the different moisture levels. The calculation was based on the minimization of the total Gibbs free energy of the multi-components and multi-phases closed system reaching chemical equilibrium. The calculation also indicated the reaction directions and tendencies of HMs components. The impacts of chlorine additives (No PVC, 1%PVC, and 5%PVC) and moisture on the behavior of HMs were investigated at different temperature levels in the system (750 °C, 950 °C, and 1150 °C). Furthermore, because the incineration temperature falls down with the increase in moisture in waste, the co-influence of moisture and temperature in combusting MSW on the HMs was also studied with the given chlorine (as 1%PVC + 0.5%NaCl). The results showed that in the non-chlorine system, the impact of the moisture on Pb, Zn, and Cu was not significant, and the ratio of compound transformation was less than 10%, except the Cd compounds at 950 °C and 1150 °C. In the system with low chlorine (as 1%PVC) at constant temperature, the chlorides of HMs (Cd, Pb, Zn, and Cu) transferred to oxides, and when the content of chlorine rose up (as 5%PVC), the ratio of the chlorides of HMs (Cd, Pb, Zn, and Cu) transferring to oxides fell down noticeably. When the moisture varied together with the temperature, the Zn and Cu compounds transferred from chlorides to oxides with increase in moisture as well as decrease in temperature. At the temperature of 700–1000 °C, the impact of temperature on Pb and Cd was little and the moisture was the main factor

  6. Brown Boveri moves to fourth generation MSRs [moisture separator reheaters

    International Nuclear Information System (INIS)

    Boeckh, P. von

    1987-01-01

    The fourth, space saving, generation of moisture separator reheaters from Brown Boveri and Cie (BBC) consists of two types of high velocity moisture separators, 'Mops' and 'Scrups', and the small size reheater, 'Road' . The design of the unit is described, together with operational experience. (author)

  7. MOISTURE IN COTTON BY THE KARL FISCHER TITRATION REFERENCE METHOD

    Science.gov (United States)

    Moisture is a critical parameter that influences many aspects of cotton fiber from harvesting and ginning to various fiber properties. Because of their importance, reference moisture methods that are more accurate than the existing oven-drying techniques and relatively easy to generate results are ...

  8. Moisture distribution computed from electrical impedance tomographic data of a bentonite clay/sand material

    International Nuclear Information System (INIS)

    Strobel, G.S.

    1995-11-01

    Moisture contents values were calculated from electrical impedance-computed tomography measurements and compared with thermocouple psychrometer moisture values. The measurements were taken, in situ and under isothermal conditions, in a bentonite clay/sand packed borehole at the Underground Research Laboratory. Two sets of impedances moisture contents were calculated from the impedance valves--independent of each other. For one set, impedance measurements were fitted to the psychrometer moisture values in a least-squares fit to a generalized calibration curve and, for the second set, an impedance-moisture relationship from laboratory calibrations was applied. The impedance-computed moisture content data showed low scatter and the trends were consistent between the three sets of values. However, the moisture content data computed from the calibration curve were more consistent with those expected from physical arguments. The moisture values from the psychrometer readings were offset and, consequently, so were those produced after applying the fitting strategy. Internal redistribution of moisture appears to have had a more significant effect on the system than did inflow at the boundary. Inflow did cause a significant change but this was localized, during this period, to the outer ∼ 0.05 m of the test hole. No comment was made as to what internal processes caused these responses. (author) 9 refs., 2 tabs., 5 figs

  9. Evaluation of AMSR-E derived soil moisture over Australia, /Remote Sensing of Environment

    NARCIS (Netherlands)

    Draper, C.S.; Walker, J.P.; Steinle, P.J.; De Jeu, R.A.M.; Holmes, T.R.H.

    2009-01-01

    This paper assesses remotely sensed near-surface soil moisture over Australia, derived from the passive microwave Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) instrument. Soil moisture fields generated by the AMSR-E soil moisture retrieval algorithm developed at the Vrije

  10. Finite element modelling of moisture related and visco-elastic deformations in inhomogeneous timber beams

    DEFF Research Database (Denmark)

    Ormarsson, Sigurdur; Dahlblom, Ola

    2013-01-01

    Wood is a hygro-mechanical, non-isotropic and inhomogeneous material concerning both modulus of elasticity (MOE) and shrinkage properties. In stress calculations associated with ordinary timber design, these matters are often not dealt with properly. The main reason for this is that stress...... and the longitudinal shrinkage coefficient vary considerably from pith to bark. The question is how much these variations affect the stress distribution in wooden structures exposed to variable moisture climate. The paper presents a finite element implementation of a beam element with the aim of studying how wooden...

  11. Compact polarimetric synthetic aperture radar for monitoring soil moisture condition

    Science.gov (United States)

    Merzouki, A.; McNairn, H.; Powers, J.; Friesen, M.

    2017-12-01

    Coarse resolution soil moisture maps are currently operationally delivered by ESA's SMOS and NASA's SMAP passive microwaves sensors. Despite this evolution, operational soil moisture monitoring at the field scale remains challenging. A number of factors contribute to this challenge including the complexity of the retrieval that requires advanced SAR systems with enhanced temporal revisit capabilities. Since the launch of RADARSAT-2 in 2007, Agriculture and Agri-Food Canada (AAFC) has been evaluating the accuracy of these data for estimating surface soil moisture. Thus, a hybrid (multi-angle/multi-polarization) retrieval approach was found well suited for the planned RADARSAT Constellation Mission (RCM) considering the more frequent relook expected with the three satellite configuration. The purpose of this study is to evaluate the capability of C-band CP data to estimate soil moisture over agricultural fields, in anticipation of the launch of RCM. In this research we introduce a new CP approach based on the IEM and simulated RCM CP mode intensities from RADARSAT-2 images acquired at different dates. The accuracy of soil moisture retrieval from the proposed multi-polarization and hybrid methods will be contrasted with that from a more conventional quad-pol approach, and validated against in situ measurements by pooling data collected over AAFC test sites in Ontario, Manitoba and Saskatchewan, Canada.

  12. Negative soil moisture-precipitation feedback in dry and wet regions.

    Science.gov (United States)

    Yang, Lingbin; Sun, Guoqing; Zhi, Lu; Zhao, Jianjun

    2018-03-05

    Soil moisture-precipitation (SM-P) feedback significantly influences the terrestrial water and energy cycles. However, the sign of the feedback and the associated physical mechanism have been debated, leaving a research gap regarding global water and climate changes. Based on Koster's framework, we estimate SM-P feedback using satellite remote sensing and ground observation data sets. Methodologically, the sign of the feedback is identified by the correlation between monthly soil moisture and next-month precipitation. The physical mechanism is investigated through coupling precipitation and soil moisture (P-SM), soil moisture ad evapotranspiration (SM-E) and evapotranspiration and precipitation (E-P) correlations. Our results demonstrate that although positive SM-P feedback is predominant over land, non-negligible negative feedback occurs in dry and wet regions. Specifically, 43.75% and 40.16% of the negative feedback occurs in the arid and humid climate zones. Physically, negative SM-P feedback depends on the SM-E correlation. In dry regions, evapotranspiration change is soil moisture limited. In wet regions, evapotranspiration change is energy limited. We conclude that the complex SM-E correlation results in negative SM-P feedback in dry and wet regions, and the cause varies based on the environmental and climatic conditions.

  13. Landscape complexity and soil moisture variation in south Georgia, USA, for remote sensing applications

    Science.gov (United States)

    Giraldo, Mario A.; Bosch, David; Madden, Marguerite; Usery, Lynn; Kvien, Craig

    2008-08-01

    SummaryThis research addressed the temporal and spatial variation of soil moisture (SM) in a heterogeneous landscape. The research objective was to investigate soil moisture variation in eight homogeneous 30 by 30 m plots, similar to the pixel size of a Landsat Thematic Mapper (TM) or Enhanced Thematic Mapper plus (ETM+) image. The plots were adjacent to eight stations of an in situ soil moisture network operated by the United States Department of Agriculture-Agriculture Research Service USDA-ARS in Tifton, GA. We also studied five adjacent agricultural fields to examine the effect of different landuses/land covers (LULC) (grass, orchard, peanuts, cotton and bare soil) on the temporal and spatial variation of soil moisture. Soil moisture field data were collected on eight occasions throughout 2005 and January 2006 to establish comparisons within and among eight homogeneous plots. Consistently throughout time, analysis of variance (ANOVA) showed high variation in the soil moisture behavior among the plots and high homogeneity in the soil moisture behavior within them. A precipitation analysis for the eight sampling dates throughout the year 2005 showed similar rainfall conditions for the eight study plots. Therefore, soil moisture variation among locations was explained by in situ local conditions. Temporal stability geostatistical analysis showed that soil moisture has high temporal stability within the small plots and that a single point reading can be used to monitor soil moisture status for the plot within a maximum 3% volume/volume (v/v) soil moisture variation. Similarly, t-statistic analysis showed that soil moisture status in the upper soil layer changes within 24 h. We found statistical differences in the soil moisture between the different LULC in the agricultural fields as well as statistical differences between these fields and the adjacent 30 by 30 m plots. From this analysis, it was demonstrated that spatial proximity is not enough to produce similar

  14. Moisture Research - Optimizing Wall Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Arena, L.; Mantha, P.

    2013-05-01

    The Consortium for Advanced Residential Buildings (CARB) evaluated several different configurations of wall assemblies to determine the accuracy of moisture modeling and make recommendations to ensure durable, efficient assemblies. WUFI and THERM were used to model the hygrothermal and heat transfer characteristics of these walls.

  15. Impacts of Soil Moisture on Typical Frontal Rainstorm in Yangtze River Basin

    Directory of Open Access Journals (Sweden)

    Jinzhong Min

    2016-03-01

    Full Text Available By using a coupled land surface-atmosphere model with initial conditions of varying resolution and ensembles of systematically changed soil moisture, convective-scale simulations of a typical frontal rainstorm in the Yangtze River Basin are collected to investigate: (1 effects of different datasets on the simulated frontal mesoscale convective systems (MCSs; (2 possible linkages between soil moisture, planetary boundary layer (PBL, MCSs and precipitation in this modeled rainstorm. Firstly, initial soil moisture differences can affect the PBL, MCSs and precipitation of this frontal rainstorm. Specially, for a 90 mm precipitation forecast, the Threat score (TS can increase 6.61% by using the Global Land Data Assimilation System (GLDAS soil moisture. Secondly, sensitivity experiment results show that the near-surface thermodynamic conditions are more sensitive to dry soil than wet due to the initial moist surface; atmosphere conditions have suppressed the relations between soil and atmosphere; and decreased precipitation can be found over both wet and dry surfaces. Generally, a positive feedback between soil moisture and the near-surface thermodynamic conditions is identified, while the relations between soil moisture and precipitation are quite complicated. This relationship shows a daytime mixing of warm surface soil over dry surfaces and a daytime evaporation of adequate moisture over wet surfaces. The large-scale forcing can affect these relations and finally cause decreased precipitation over both wet and dry surfaces.

  16. Incorporation of Passive Microwave Brightness Temperatures in the ECMWF Soil Moisture Analysis

    Directory of Open Access Journals (Sweden)

    Joaquín Muñoz-Sabater

    2015-05-01

    Full Text Available For more than a decade, the European Centre for Medium-Range Weather Forecasts (ECMWF has used in-situ observations of 2 m temperature and 2 m relative humidity to operationally constrain the temporal evolution of model soil moisture. These observations are not available everywhere and they are indirectly linked to the state of the surface, so under various circumstances, such as weak radiative forcing or strong advection, they cannot be used as a proxy for soil moisture reinitialization in numerical weather prediction. Recently, the ECMWF soil moisture analysis has been updated to be able to account for the information provided by microwave brightness temperatures from the Soil Moisture and Ocean Salinity (SMOS mission of the European Space Agency (ESA. This is the first time that ECMWF uses direct information of the soil emission from passive microwave data to globally adjust the estimation of soil moisture by a land-surface model. This paper presents a novel version of the ECMWF Extended Kalman Filter soil moisture analysis to account for remotely sensed passive microwave data. It also discusses the advantages of assimilating direct satellite radiances compared to current soil moisture products, with a view to an operational implementation. A simple assimilation case study at global scale highlights the potential benefits and obstacles of using this new type of information in a global coupled land-atmospheric model.

  17. A study of quantitative radiography for moisture content distributions in plant

    International Nuclear Information System (INIS)

    Kawabata, Y.; Hino, M.; Horie, T.

    2003-01-01

    Vacuum pre-cooling in cut flower or perishable vegetables industry are used for protecting from the deterioration of the perishables during transportation. Some improvements of the pre-cooling way, however, are required for a bruise in plant on the way of handling. Neutron radiography is suitable to detect and observe the bruise in plant, especially, moisture content distributions in leaves, flowers and stalks. Neutron spectrum in irradiation neutron beams is required for obtaining quantitative moisture contents in plant. The neutron spectrum measurements for determination of effective cross-section of water are carried out at CN-3 experimental hole of Kyoto University Reactor (KUR) by time of flight method. Moisture content distributions in leaves of chrysanthemum, before and after the vacuum pre-cooling are measured by cold neutron radiography at the experimental hole. The local decreases of moisture contents caused by a bruise on the surface of the leaves are measured quantitatively by the cold neutron radiography. The quantitative changes of the moisture content in the leaves are able to read out from the cold neutron radiography image. (M. Suetake)

  18. Precipitation Estimation Using L-Band and C-Band Soil Moisture Retrievals

    Science.gov (United States)

    Koster, Randal D.; Brocca, Luca; Crow, Wade T.; Burgin, Mariko S.; De Lannoy, Gabrielle J. M.

    2016-01-01

    An established methodology for estimating precipitation amounts from satellite-based soil moisture retrievals is applied to L-band products from the Soil Moisture Active Passive (SMAP) and Soil Moisture and Ocean Salinity (SMOS) satellite missions and to a C-band product from the Advanced Scatterometer (ASCAT) mission. The precipitation estimates so obtained are evaluated against in situ (gauge-based) precipitation observations from across the globe. The precipitation estimation skill achieved using the L-band SMAP and SMOS data sets is higher than that obtained with the C-band product, as might be expected given that L-band is sensitive to a thicker layer of soil and thereby provides more information on the response of soil moisture to precipitation. The square of the correlation coefficient between the SMAP-based precipitation estimates and the observations (for aggregations to approximately100 km and 5 days) is on average about 0.6 in areas of high rain gauge density. Satellite missions specifically designed to monitor soil moisture thus do provide significant information on precipitation variability, information that could contribute to efforts in global precipitation estimation.

  19. THE INFLUENCE OF RAW MATERIAL ON THE LIQUID MOISTURE TRANSPORT THROUGH KNITTED FABRIC

    Directory of Open Access Journals (Sweden)

    COLDEA Alina

    2014-05-01

    Full Text Available The comfort is undoubtedly the most important human attribute depends upon the moisture transport which in turn depends on the moisture transport behavior of the knitted fabric. Moisture transport is the transfer of liquid water capillary interstices of the yarns and depends on the wettability of fiber surfaces, as well as the structure of the yarn and fabric. Because of its good water absorption property, cotton is often used for next-to-skin wear such as t-shirts, underwear, socks. All these are known as ``moisture management`` which means the ability of a textile fabric to transport moisture away from the skin to the garment’s outer surface in multi-dimensions and it is one of the key performance criteria in today’s apparel industry since it has a significant effect on the human perception of moisture sensations. In order to study, plated knitted fabric for socks were knitted as plated single jersey in the same production conditions, from different types of yarns, produced in different yarn counts (Ne 20, Ne 24, Ne 30 and different raw material. (cotton, bamboo, soybean, polyester, viscose. Were chose two different density on circular knitting machine. The liquid moisture management of the samples was measured in order to determinate moisture transport index. Was study also the influence of raw material and fabric structure related to the moisture transport index. According to the obtained results, it was found that some of the knitted fabrics used in this study have goodmoisture management capability.

  20. Reliability and service life of wood structures and buildings

    Directory of Open Access Journals (Sweden)

    Zdeňka Havířová

    2005-01-01

    Full Text Available Service life of constructions and buildings of wood is dependent on temperature and moisture conditions in layers of the building cladding where the wood framework is built in. Temperature/moisture conditions or the corresponding equilibrium moisture content (EMC of the construction show considerable effects on the functional reliability of the whole building from the viewpoint of mechanical resistance and stability (ER1, energy savings and thermal protection (ER6 and hygiene, health and environment protection (ER3. To ensure the reliability of constructions and buildings for the period of their supposed service life a more profound analysis of constructions is necessary from the aspect of a global thermal/technical evaluation.