[CO2 response process and its simulation of Prunus sibirica photosynthesis under different soil moisture conditions].

Science.gov (United States)

Wu, Qin; Zhang, Guang-Can; Pei, Bin; Xu, Zhi-Qiang; Zhao, Yu; Fang, Li-Dong

2013-06-01

Taking the two-year old potted Prunus sibirica seedlings as test materials, and using CIRAS-2 photosynthetic system, this paper studied the CO2 response process of P. sibirica photosynthesis in semi-arid loess hilly region under eight soil moisture conditions. The CO2 response data of P. sibirica were fitted and analyzed by rectangular hyperbola model, exponential equation, and modified rectangular hyperbola model. Meanwhile, the quantitative relationships between the photosynthesis and the soil moisture were discussed. The results showed that the CO2 response process of P. sibirica photosynthesis had obvious response characteristics to the soil moisture threshold. The relative soil water content (RWC) required to maintain the higher photosynthetic rate (P(n)) and carboxylation efficiency (CE) of P. sibirica was in the range of 46.3%-81.9%. In this RWC range, the photosynthesis did not appear obvious CO2 saturated inhibition phenomenon. When the RWC exceeded this range, the photosynthetic capacity (P(n max)), CE, and CO2 saturation point (CSP) decreased evidently. Under different soil moisture conditions, there existed obvious differences among the three models in simulating the CO2 response data of P. sibirica. When the RWC was in the range of 46.3%-81.9%, the CO2 response process and the characteristic parameters such as CE, CO2 compensation point (see symbol), and photorespiration rate (R(p)) could be well fitted by the three models, and the accuracy was in the order of modified rectangular hyperbola model > exponential equation > rectangular hyperbola model. When the RWC was too high or too low, namely, the RWC was > 81.9% or CO2 response process and the characteristic parameters. It was suggested that when the RWC was from 46.3% to 81.9%, the photosynthetic efficiency of P. sibirica was higher, and, as compared with rectangular hyperbola model and exponential equation, modified rectangular hyperbola model had more applicability to fit the CO2 response data of

The moisture conditions of nuclear reactor concrete containment walls - an example for a BWR reactor

Energy Technology Data Exchange (ETDEWEB)

Nilsson, L.O.; Johansson, P. [Lund Institute of Technology, Laboratory of Building Materials, PO Box 118, 221 00 Lund (Sweden)

2006-07-01

A method is presented on how to quantify the moisture conditions of nuclear concrete containment walls. The method is based on first quantifying the boundary conditions at the outer and inner surfaces and then describing the moisture fixation and moisture transport within the concrete wall. The temperature and humidity conditions of the outdoor air and of the air close to the wall surfaces are monitored for a period of time and the vapour contents in the different points are compared. From the differences between the vapour contents the sources of moisture are identified and quantified. The previous and future climatic conditions are then predicted. An example is given for the conditions in the containment walls at Barsebaeck nuclear power plant, where moisture measurements have been performed in situ and on samples taken from the walls. (authors)

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...

Assessment of initial soil moisture conditions for event-based rainfall-runoff modelling

OpenAIRE

Tramblay, Yves; Bouvier, Christophe; Martin, C.; Didon-Lescot, J. F.; Todorovik, D.; Domergue, J. M.

2010-01-01

Flash floods are the most destructive natural hazards that occur in the Mediterranean region. Rainfall-runoff models can be very useful for flash flood forecasting and prediction. Event-based models are very popular for operational purposes, but there is a need to reduce the uncertainties related to the initial moisture conditions estimation prior to a flood event. This paper aims to compare several soil moisture indicators: local Time Domain Reflectometry (TDR) measurements of soil moisture,...

Topsoil moisture mapping using geostatistical techniques under different Mediterranean climatic conditions.

Science.gov (United States)

Martínez-Murillo, J F; Hueso-González, P; Ruiz-Sinoga, J D

2017-10-01

Soil mapping has been considered as an important factor in the widening of Soil Science and giving response to many different environmental questions. Geostatistical techniques, through kriging and co-kriging techniques, have made possible to improve the understanding of eco-geomorphologic variables, e.g., soil moisture. This study is focused on mapping of topsoil moisture using geostatistical techniques under different Mediterranean climatic conditions (humid, dry and semiarid) in three small watersheds and considering topography and soil properties as key factors. A Digital Elevation Model (DEM) with a resolution of 1×1m was derived from a topographical survey as well as soils were sampled to analyzed soil properties controlling topsoil moisture, which was measured during 4-years. Afterwards, some topography attributes were derived from the DEM, the soil properties analyzed in laboratory, and the topsoil moisture was modeled for the entire watersheds applying three geostatistical techniques: i) ordinary kriging; ii) co-kriging considering as co-variate topography attributes; and iii) co-kriging ta considering as co-variates topography attributes and gravel content. The results indicated topsoil moisture was more accurately mapped in the dry and semiarid watersheds when co-kriging procedure was performed. The study is a contribution to improve the efficiency and accuracy of studies about the Mediterranean eco-geomorphologic system and soil hydrology in field conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Frost damage of roof tiles: A study on moisture boundary conditions

OpenAIRE

Iba, Chiemi; Ueda, Ayumi; Hokoi, Shuichi

2015-01-01

Freeze-thaw cycles are the most serious cause of roof tile deterioration; thus, it is important to know the temperature and moisture distributions in tile materials for protection against frost damage. This study focused on moisture boundary conditions for air layers under the tile. Temperature and humidity were measured using model structures with different types of roof tiles. The results showed that the temperatures around the roof were strongly influenced by solar and longwave radiation, ...

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.

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.

Predicting temperature and moisture distributions in conditioned spaces using the zonal approach

Energy Technology Data Exchange (ETDEWEB)

Mendonca, K.C. [Parana Pontifical Catholic Univ., Curitiba (Brazil); Wurtz, E.; Inard, C. [La Rochelle Univ., La Rochelle, Cedex (France). LEPTAB

2005-07-01

Moisture interacts with building elements in a number of different ways that impact upon building performance, causing deterioration of building materials, as well as contributing to poor indoor air quality. In humid climates, moisture represents one of the major loads in conditioned spaces. It is therefore important to understand and model moisture transport accurately. This paper discussed an intermediate zonal approach to building a library of data in order to predict whole hygrothermal behavior in conditioned rooms. The zonal library included 2 models in order to consider building envelope moisture buffering effects as well as taking into account the dynamic aspect of jet airflow in the zonal method. The zonal library was then applied to a case study to show the impact of external humidity on the whole hygrothermal performance of a room equipped with a vertical fan-coil unit. The proposed theory was structured into 3 groups representing 3 building domains: indoor air; envelope; and heating, ventilation and air conditioning (HVAC) systems. The indoor air sub-model related to indoor air space, where airflow speed was considered to be low. The envelope sub-model related to the radiation exchanges between the envelope and its environment as well as to the heat and mass transfers through the envelope material. The HVAC system sub-model referred to the whole system including equipment, control and specific airflow from the equipment. All the models were coupled into SPARK, where the resulting set of non-linear equations were solved simultaneously. A case study of a large office conditioned by a vertical fan-coil unit with a rectangular air supply diffuser was presented. Details of the building's external and internal environment were provided, as well as convective heat and mass transfer coefficients and temperature distributions versus time. Results of the study indicated that understanding building material moisture buffering effects is as important as

Weathering processes under various moisture conditions in a lignite mine spoil from As Pontes (N.W. Spain)

International Nuclear Information System (INIS)

Seoane, S.; Leiros, M.C.

1997-01-01

Processes contributing to acid release/consumption during weathering of a lignite mine spoil (2.3% w/w S as sulfides) from As Pontes (N.W. Spain) were studied under three moisture conditions (at field capacity or under alternate wetting-drying or forced percolation), which were simulated in laboratory experiments. Oxidation of sulfides to sulfates was favoured under all three moisture conditions, releasing most acid in spoil kept at field capacity. Hydroxysulfates formed in spoil kept at field capacity or under alternate wetting-drying conditions, thereby contributing to acid release. Acid consumption by dissolution of clay minerals, especially micas, was favoured under all three moisture conditions, but was particularly intense in spoil at field capacity. Dissolution of aluminium oxides was also favoured under all the moisture conditions studied. 27 refs., 8 figs., 6 tabs

Changes in seed water status as characterized by NMR in developing soybean seed grown under moisture stress conditions

International Nuclear Information System (INIS)

Krishnan, P.; Singh, Ravender; Verma, A.P.S.; Joshi, D.K.; Singh, Sheoraj

2014-01-01

Highlights: • In developing soybean seeds, moisture stress resulted in more proportion of water to bound state. • These changes are further corroborated by concomitant changes in seed metabolites. • Thus there exists a moisture stress and development stage dependence of seed tissue water status. - Abstract: Changes in water status of developing seeds of Soybean (Glycine max L. Merrill.) grown under different moisture stress conditions were characterized by proton nuclear magnetic resonance (NMR)- spin–spin relaxation time (T 2 ). A comparison of the seed development characteristics, composition and physical properties indicated that, characteristics like seed weight, seed number/ear, rate of seed filling increased with development stages but decreased with moisture stress conditions. The NMR- spin–spin relaxation (T 2 ) component like bound water increased with seed maturation (40–50%) but decreased with moisture stress conditions (30–40%). The changes in seed water status to increasing levels of moisture stress and seed maturity indicates that moisture stress resulted in more proportion of water to bound state and intermediate state and less proportion of water in free-state. These changes are further corroborated by significant changes in protein and starch contents in seeds under high moisture stress treatments. Thus seed water status during its development is not only affected by development processes but also by moisture stress conditions. This study strongly indicated a clear moisture stress and development stage dependence of seed tissue water status in developing soybean seeds

Changes in seed water status as characterized by NMR in developing soybean seed grown under moisture stress conditions

Energy Technology Data Exchange (ETDEWEB)

Krishnan, P., E-mail: pkrishnan@iari.res.in; Singh, Ravender; Verma, A.P.S.; Joshi, D.K.; Singh, Sheoraj

2014-02-21

Highlights: • In developing soybean seeds, moisture stress resulted in more proportion of water to bound state. • These changes are further corroborated by concomitant changes in seed metabolites. • Thus there exists a moisture stress and development stage dependence of seed tissue water status. - Abstract: Changes in water status of developing seeds of Soybean (Glycine max L. Merrill.) grown under different moisture stress conditions were characterized by proton nuclear magnetic resonance (NMR)- spin–spin relaxation time (T{sub 2}). A comparison of the seed development characteristics, composition and physical properties indicated that, characteristics like seed weight, seed number/ear, rate of seed filling increased with development stages but decreased with moisture stress conditions. The NMR- spin–spin relaxation (T{sub 2}) component like bound water increased with seed maturation (40–50%) but decreased with moisture stress conditions (30–40%). The changes in seed water status to increasing levels of moisture stress and seed maturity indicates that moisture stress resulted in more proportion of water to bound state and intermediate state and less proportion of water in free-state. These changes are further corroborated by significant changes in protein and starch contents in seeds under high moisture stress treatments. Thus seed water status during its development is not only affected by development processes but also by moisture stress conditions. This study strongly indicated a clear moisture stress and development stage dependence of seed tissue water status in developing soybean seeds.

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....

The importance of moisture buffering for indoor climate and energy conditions of buildings

DEFF Research Database (Denmark)

Rode, Carsten; Grau, Karl

2007-01-01

A new Nordic test method specifies a test protocol for determination of the so-called Moisture Buffer Value (MBV) of building materials. But how important is moisture buffering to determine the indoor humidity condition of buildings? The paper will present the new MBV-definition. Although...... buffering to save energy by reducing the requirement for ventilation in periods, and still maintain the same quality of the indoor climate? The paper will outline some possibilities for analytical/numerical calculations, and will answer some of the posed questions on the probable benefit of taking moisture...

Analysis of the Dynamic Wheel Loads in Railway Transition Zones Considering the Moisture Condition of the Ballast and Subballast

Directory of Open Access Journals (Sweden)

Haoyu Wang

2017-11-01

Full Text Available Transition zones in railway tracks are the locations with considerable changes in vertical support structures, e.g., near bridges. Due to possible water flow constrictions in transition zone structures, there is frequently an increased moisture level in the ballast/subballast layers, which is a potential source of track degradation. This paper presents results of the moisture condition measured in three transition zones using ground penetrating radar, where the ballast/subballast are analyzed. The relationship between the moisture condition and track degradation in the transition zones is studied by comparing it to the longitudinal track level that is measured by the track inspection coaches. A strong connection is found between the high moisture condition and track degradation in the transition zones. The dynamic behavior of the transition zones with high moisture condition is analyzed using the Finite Element method. Differential stiffness and settlement are taken into consideration in the transition zone model, which is also coupled with a vehicle. The ballast/subballast layers are modelled as solid elements. Increased moisture conditions are considered as a reduction of elastic modulus, according to laboratory findings. Results show that high moisture leads to an increase of dynamic wheel loads in the transition zone, which explains the connection and confirms that the high moisture condition is a source of transition zone problems.

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

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...

Applicability of common stomatal conductance models in maize under varying soil moisture conditions.

Science.gov (United States)

Wang, Qiuling; He, Qijin; Zhou, Guangsheng

2018-07-01

In the context of climate warming, the varying soil moisture caused by precipitation pattern change will affect the applicability of stomatal conductance models, thereby affecting the simulation accuracy of carbon-nitrogen-water cycles in ecosystems. We studied the applicability of four common stomatal conductance models including Jarvis, Ball-Woodrow-Berry (BWB), Ball-Berry-Leuning (BBL) and unified stomatal optimization (USO) models based on summer maize leaf gas exchange data from a soil moisture consecutive decrease manipulation experiment. The results showed that the USO model performed best, followed by the BBL model, BWB model, and the Jarvis model performed worst under varying soil moisture conditions. The effects of soil moisture made a difference in the relative performance among the models. By introducing a water response function, the performance of the Jarvis, BWB, and USO models improved, which decreased the normalized root mean square error (NRMSE) by 15.7%, 16.6% and 3.9%, respectively; however, the performance of the BBL model was negative, which increased the NRMSE by 5.3%. It was observed that the models of Jarvis, BWB, BBL and USO were applicable within different ranges of soil relative water content (i.e., 55%-65%, 56%-67%, 37%-79% and 37%-95%, respectively) based on the 95% confidence limits. Moreover, introducing a water response function, the applicability of the Jarvis and BWB models improved. The USO model performed best with or without introducing the water response function and was applicable under varying soil moisture conditions. Our results provide a basis for selecting appropriate stomatal conductance models under drought conditions. Copyright © 2018 Elsevier B.V. All rights reserved.

Influence of moisture condition on chloride diffusion in partially saturated ordinary Portland cement mortar

NARCIS (Netherlands)

Zhang, Y.; Zhang, M.; Ye, G.

2018-01-01

Experiments have been carried out to study the influence of moisture condition, including moisture content and its distribution, on the chloride diffusion in partially saturated ordinary Portland cement mortar. The mortar samples with water-to-cement (w/c) ratios of 0.4, 0.5 and 0.6, cured for 1

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.

Creep of concrete under various temperature, moisture, and loading conditions

International Nuclear Information System (INIS)

McDonald, J.E.

1976-01-01

An investigation was conducted to obtain information on the time-dependent deformation behavior of concrete in the presence of temperature, moisture, and loading conditions similar to those encountered in a prestressed concrete reactor vessel (PCRV). Variables included concrete strength, aggregate types, curing history, temperature, and types of loading (uniaxial, hydrostatic, biaxial, and triaxial). There were 66 test conditions for creep tests and 12 test conditions for unloaded or control specimens. Experimental results are presented and discussed. Comparisons are made concerning the effect of the various test conditions on the behavior of concrete, and general conclusions are formulated

Testate amoebae communities sensitive to surface moisture conditions in Patagonian peatlands

Science.gov (United States)

Loisel, J.; Booth, R.; Charman, D.; van Bellen, S.; Yu, Z.

2017-12-01

Here we examine moss surface samples that were collected during three field campaigns (2005, 2010, 2014) across southern Patagonian peatlands to assess the potential use of testate amoebae and 13C isotope data as proxy indicators of soil moisture. These proxies have been widely tested across North America, but their use as paleoecological tools remains sparse in the southern hemisphere. Samples were collected along a hydrological gradient spanning a range of water table depth from 0cm in wet hollows to over 85cm in dry hummocks. Moss moisture content was measured in the field. Over 25 taxa were identified, with many of them not found in North America. Ordinations indicate statistically significant and dominant effects of soil moisture and water table depth on testate assemblages, though interestingly 13C is even more strongly correlated with testates amoebae than direct soil conditions. It is possible that moss 13C signature constitutes a compound indicator that represents seasonal soil moisture better than opportunistic sampling during field campaigns. There is no significant effect of year or site across the dataset. In addition to providing a training set that translates testate amoebae moisture tolerance range into water tabel depth for Patagonian peatlands, we also compare our results with those from the North American training set to show that, despite 'novel' Patagonian taxa, the robustness of international training sets is probably sufficient to quantify most changes in soil moisture from any site around the world. We also identify key indicator species that are shown to be of universal value in peat-based hydrological reconstructions.

Perturbations in the initial soil moisture conditions: Impacts on hydrologic simulation in a large river basin

Science.gov (United States)

Niroula, Sundar; Halder, Subhadeep; Ghosh, Subimal

2018-06-01

Real time hydrologic forecasting requires near accurate initial condition of soil moisture; however, continuous monitoring of soil moisture is not operational in many regions, such as, in Ganga basin, extended in Nepal, India and Bangladesh. Here, we examine the impacts of perturbation/error in the initial soil moisture conditions on simulated soil moisture and streamflow in Ganga basin and its propagation, during the summer monsoon season (June to September). This provides information regarding the required minimum duration of model simulation for attaining the model stability. We use the Variable Infiltration Capacity model for hydrological simulations after validation. Multiple hydrologic simulations are performed, each of 21 days, initialized on every 5th day of the monsoon season for deficit, surplus and normal monsoon years. Each of these simulations is performed with the initial soil moisture condition obtained from long term runs along with positive and negative perturbations. The time required for the convergence of initial errors is obtained for all the cases. We find a quick convergence for the year with high rainfall as well as for the wet spells within a season. We further find high spatial variations in the time required for convergence; the region with high precipitation such as Lower Ganga basin attains convergence at a faster rate. Furthermore, deeper soil layers need more time for convergence. Our analysis is the first attempt on understanding the sensitivity of hydrological simulations of Ganga basin on initial soil moisture conditions. The results obtained here may be useful in understanding the spin-up requirements for operational hydrologic forecasts.

Screening variability and change of soil moisture under wide-ranging climate conditions: Snow dynamics effects.

Science.gov (United States)

Verrot, Lucile; Destouni, Georgia

2015-01-01

Soil moisture influences and is influenced by water, climate, and ecosystem conditions, affecting associated ecosystem services in the landscape. This paper couples snow storage-melting dynamics with an analytical modeling approach to screening basin-scale, long-term soil moisture variability and change in a changing climate. This coupling enables assessment of both spatial differences and temporal changes across a wide range of hydro-climatic conditions. Model application is exemplified for two major Swedish hydrological basins, Norrström and Piteälven. These are located along a steep temperature gradient and have experienced different hydro-climatic changes over the time period of study, 1950-2009. Spatially, average intra-annual variability of soil moisture differs considerably between the basins due to their temperature-related differences in snow dynamics. With regard to temporal change, the long-term average state and intra-annual variability of soil moisture have not changed much, while inter-annual variability has changed considerably in response to hydro-climatic changes experienced so far in each basin.

Bioactivity of Several Herbicides on the Nanogram Level Under Different Soil Moisture Conditions.

Science.gov (United States)

Jung, S C; Kuk, Y I; Senseman, S A; Ahn, H G; Seong, C N; Lee, D J

2015-01-01

In this study, a double-tube centrifuge method was employed to determine the effects of soil moisture on the bioactivity of cafenstrole, pretilachlor, benfuresate, oxyfluorfen and simetryn. In general, the available herbicide concentration in soil solution (ACSS) showed little change as soil moisture increased for herbicides. The total available herbicide in soil solution (TASS) typically increased as soil moisture increased for all herbicides. The relationship between TASS and % growth rate based on dry weight showed strong linear relationships for both cafenstrole and pretilachlor, with r2 values of 0.95 and 0.84, respectively. Increasing TASS values were consistent with increasing herbicide water solubility, with the exception of the ionizable herbicide simetryn. Plant absorption and % growth rate exhibited a strong linear relationship with TASS. According to the results suggested that TASS was a better predictor of herbicidal bioactivity than ACSS for all herbicides under unsaturated soil moisture conditions.

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...

The effects of a reduced balanced protein diet on litter moisture, pododermatitis and feather condition of female broiler breeders over three generations.

Science.gov (United States)

Li, C; Lesuisse, J; Schallier, S; Clímaco, W; Wang, Y; Bautil, A; Everaert, N; Buyse, J

2017-11-02

Protein content reduction in broiler breeder diets has been increasingly investigated. However, broiler breeders reared on low protein diets are characterized by a deterioration of the feather condition. Furthermore, polydipsia induced by controlled feed intake increases litter moisture and as a consequence pododermatitis. This project aimed to study the litter moisture, pododermatitis and feather condition of breeders fed with a 25% reduced balanced protein (RP) diet during the rearing and laying period over three successive generations. The experiment started with two treatments for the F0 generation: control (C) group fed with standard C diets and RP group fed with RP diets. The female F0-progeny of each treatment was divided into the two dietary treatments as well, resulting in four treatments for the F1 generation: C/C, C/RP, RP/C and RP/RP (breeder feed in F0/F1 generation). The RP diet fed breeders received on average 10% more feed than C diet fed breeders to achieve the same target BW. The female F1-progeny of each treatment were all fed with C diets which resulted in four treatments for the F2 generation: C/C/C, C/RP/C, RP/C/C and RP/RP/C (breeder feed in F0/F1/F2 generation). Litter moisture, footpad and hock dermatitis were recorded at regular intervals throughout the experimental period in all three generations. For the F0 and F1 generation, the pens of breeders receiving C diets had significantly higher litter moisture than the RP diets fed groups (Pdiets had poorer feather condition than those receiving the C diets (Pdiets to broiler breeders improved litter condition and hence reduced FDO whereas impaired feather condition. Furthermore, positive transgenerational effects of the maternal RP diets on the feather condition may be inferred, hence potentially altering the welfare status.

Mercury critical concentrations to Enchytraeus crypticus (Annelida: Oligochaeta) under normal and extreme conditions of moisture in tropical soils - Reproduction and survival.

Science.gov (United States)

Buch, Andressa Cristhy; Schmelz, Rüdiger M; Niva, Cintia Carla; Correia, Maria Elizabeth Fernandes; Silva-Filho, Emmanoel Vieira

2017-05-01

Soil provides many ecosystem services that are essential to maintain its quality and healthy development of the flora, fauna and human well-being. Environmental mercury levels may harm the survival and diversity of the soil fauna. In this respect, efforts have been made to establish limit values of mercury (Hg) in soils to terrestrial fauna. Soil organisms such as earthworms and enchytraeids have intimate contact with trace metals in soil by their oral and dermal routes, reflecting the potentially adverse effects of this contaminant. The main goal of this study was to obtain Hg critical concentrations under normal and extreme conditions of moisture in tropical soils to Enchytraeus crypticus to order to assess if climate change may potentiate their acute and chronic toxicity effects. Tropical soils were sampled from of two Forest Conservation Units of the Rio de Janeiro State - Brazil, which has been contaminated by Hg atmospheric depositions. Worms were exposed to three moisture conditions, at 20%, 50% and 80% of water holding capacity, respectively, and in combination with different Hg (HgCl 2 ) concentrations spiked in three types of tropical soil (two natural soils and one artificial soil). The tested concentrations ranged from 0 to 512mg Hg kg -1 dry weight. Results indicate that the Hg toxicity is higher under increased conditions of moisture, significantly affecting survival and reproduction rate. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

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)

[Sap flow characteristics of Quercus liaotungensis in response to sapwood area and soil moisture in the loess hilly region, China].

Science.gov (United States)

Lyu, Jin Lin; He, Qiu Yue; Yan, Mei Jie; Li, Guo Qing; Du, Sheng

2018-03-01

To examine the characteristics of sap flow in Quercus liaotungensis and their response to environmental factors under different soil moisture conditions, Granier-type thermal dissipation probes were used to measure xylem sap flow of trees with different sapwood area in a natural Q. liaotungensis forest in the loess hilly region. Solar radiation, air temperature, relative air humidity, precipitation, and soil moisture were monitored during the study period. The results showed that sap flux of Q. liaotungensis reached daily peaks earlier than solar radiation and vapor pressure deficit. The diurnal dynamics of sap flux showed a similar pattern to those of the environmental factors. Trees had larger sap flux during the period with higher soil moisture. Under the same soil moisture conditions, trees with larger diameter and sapwood areas had significantly higher sap flux than those with smaller diameter and sapwood areas. Sap flux could be fitted with vapor pressure deficit, solar radiation, and the integrated index of the two factors using exponential saturation function. Differences in the fitted curves and parameters suggested that sap flux tended to reach saturation faster under higher soil moisture. Furthermore, trees in the smaller diameter class were more sensitive to the changes of soil moisture. The ratio of daily sap flux per unit vapor pressure deficit under lower soil moisture condition to that under higher soil moisture condition was linearly correlated to sapwood area. The regressive slope in smaller diameter class was larger than that in bigger diameter class, which further indicated the higher sensitivity of trees with smaller diameter class to soil moisture. These results indicated that wider sapwood of larger diameter class provided a buffer against drought stress.

Effects of moisture conditions of dental enamel surface on bond strength of brackets bonded with moisture-insensitive primer adhesive system.

Science.gov (United States)

Endo, Toshiya; Ozoe, Rieko; Sanpei, Sugako; Shinkai, Koichi; Katoh, Yoshiroh; Shimooka, Shohachi

2008-07-01

The purposes of this study were to evaluate the effects of different degrees of water contamination on the shear bond strength of orthodontic brackets bonded to dental enamel with a moisture-insensitive primer (MIP) adhesive system and to compare the modes of bracket/adhesive failure. A total of 68 human premolars were divided into four groups by primers and enamel surface conditions (desiccated, blot dry, and overwet). In group I, the hydrophobic Transbond XT primer adhesive system was used under desiccated conditions for bonding the brackets; in group II, the hydrophilic Transbond MIP adhesive system was used under desiccated conditions; in group III, the hydrophilic Transbond MIP adhesive system was used under blot dry conditions; and in group IV, the hydrophilic Transbond MIP adhesive system was used under overwet conditions. Shear bond strength was measured with a universal testing machine, and the mode of bracket/adhesive failure was determined according to the adhesive remnant index. The mean shear bond strengths were not significantly different among groups I, II, and III, and were higher than the clinically required range of 6 to 8 MPa. The mean shear bond strength achieved in group IV was significantly lower than that achieved in groups I, II, and III, and also lower than the clinically required values. Bond failure occurred at the enamel-adhesive interface more frequently in group IV than in groups I and III. To achieve clinically sufficient bond strengths with the hydrophilic MIP adhesive system, excess water should be blotted from the water-contaminated enamel surface.

Comparison of safflower oil extraction kinetics under two characteristic moisture conditions: statistical analysis of non-linear model parameters

Directory of Open Access Journals (Sweden)

E. Baümler

2014-06-01

Full Text Available In this study the kinetics of oil extraction from partially dehulled safflower seeds under two moisture conditions (7 and 9% dry basis was investigated. The extraction assays were performed using a stirred batch system, thermostated at 50 ºC, using n-hexane as solvent. The data obtained were fitted to a modified diffusion model in order to represent the extraction kinetics. The model took into account a washing and a diffusive step. Fitting parameters were compared statistically for both moisture conditions. The oil yield increased with the extraction time in both cases, although the oil was released at different rates. A comparison of the parameters showed that both the portion extracted in the washing phase and the effective diffusion coefficient were moisture-dependent. The effective diffusivities were 2.81 10-12 and 8.06 10-13 m²s-1 for moisture contents of 7% and 9%, respectively.

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

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.

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

Robust Initial Wetness Condition Framework of an Event-Based Rainfall–Runoff Model Using Remotely Sensed Soil Moisture

Directory of Open Access Journals (Sweden)

Wooyeon Sunwoo

2017-01-01

Full Text Available Runoff prediction in limited-data areas is vital for hydrological applications, such as the design of infrastructure and flood defenses, runoff forecasting, and water management. Rainfall–runoff models may be useful for simulation of runoff generation, particularly event-based models, which offer a practical modeling scheme because of their simplicity. However, there is a need to reduce the uncertainties related to the estimation of the initial wetness condition (IWC prior to a rainfall event. Soil moisture is one of the most important variables in rainfall–runoff modeling, and remotely sensed soil moisture is recognized as an effective way to improve the accuracy of runoff prediction. In this study, the IWC was evaluated based on remotely sensed soil moisture by using the Soil Conservation Service-Curve Number (SCS-CN method, which is one of the representative event-based models used for reducing the uncertainty of runoff prediction. Four proxy variables for the IWC were determined from the measurements of total rainfall depth (API5, ground-based soil moisture (SSMinsitu, remotely sensed surface soil moisture (SSM, and soil water index (SWI provided by the advanced scatterometer (ASCAT. To obtain a robust IWC framework, this study consists of two main parts: the validation of remotely sensed soil moisture, and the evaluation of runoff prediction using four proxy variables with a set of rainfall–runoff events in the East Asian monsoon region. The results showed an acceptable agreement between remotely sensed soil moisture (SSM and SWI and ground based soil moisture data (SSMinsitu. In the proxy variable analysis, the SWI indicated the optimal value among the proposed proxy variables. In the runoff prediction analysis considering various infiltration conditions, the SSM and SWI proxy variables significantly reduced the runoff prediction error as compared with API5 by 60% and 66%, respectively. Moreover, the proposed IWC framework with

Assessment of the Swelling Pressure of the Green Clay of Tangier (Morocco Compared with the Soil-Moisture Conditions

Directory of Open Access Journals (Sweden)

El Bahlouli Tarik

2014-04-01

Full Text Available The swelling phenomenon appears seriously when changing the soil-moisture conditions. The swelling pressure induced by the expansive soil can causes unfavourable problems or instability for the civil structures. So, understanding the soil behavior is considered a valuable work for engineers and consultants in the geotechnical and civil engineering sectors. In reality, the assessment of the swelling pressure of expansive soil depends, first of all, of test conditions related to the change of soil-moisture, as it happens, the influence of the combination “loading-start wetting” and also the unloading process after saturation. To this end, we establish an experimental study on the green clay of Tangier to evaluate the swelling pressure by using oedometer apparatus. Secondly, attention is bore to the combination “initial water content-dry density”, another factor related to the change of the soil-moisture, to show the influence of initial state condition on the swelling pressure.

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.

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...

Pupal development of Ceratitis capitata (Diptera: Tephritidae) and Diachasmimorpha longicaudata (Hymenoptera: Braconidae) at different moisture values in four soil types.

Science.gov (United States)

Bento, F de M M; Marques, R N; Costa, M L Z; Walder, J M M; Silva, A P; Parra, J R P

2010-08-01

This study aimed to evaluate adult emergence and duration of the pupal stage of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and emergence of the fruit fly parasitoid, Diachasmimorpha longicaudata (Ashmead), under different moisture conditions in four soil types, using soil water matric potential. Pupal stage duration in C. capitata was influenced differently for males and females. In females, only soil type affected pupal stage duration, which was longer in a clay soil. In males, pupal stage duration was individually influenced by moisture and soil type, with a reduction in pupal stage duration in a heavy clay soil and in a sandy clay, with longer duration in the clay soil. As matric potential decreased, duration of the pupal stage of C. capitata males increased, regardless of soil type. C. capitata emergence was affected by moisture, regardless of soil type, and was higher in drier soils. The emergence of D. longicaudata adults was individually influenced by soil type and moisture factors, and the number of emerged D. longicaudata adults was three times higher in sandy loam and lower in a heavy clay soil. Always, the number of emerged adults was higher at higher moisture conditions. C. capitata and D. longicaudata pupal development was affected by moisture and soil type, which may facilitate pest sampling and allow release areas for the parasitoid to be defined under field conditions.

Productivity and seed health of husked oats (Avena sativa L. grown under different soil moisture conditions

Directory of Open Access Journals (Sweden)

Agnieszka Pszczółkowska

2012-12-01

Full Text Available The present study investigated the effect of different soil moisture content levels (60 - 70% SWC (soil water capacity - control; 30 - 35% SWC - water stress on yields, gas exchange parameters, seed health, and protein fractions of husked oat grain. The study showed that water deficit resulted in a decrease in grain weight per plant and a reduction in the gas exchange rates, primarily the photosynthesis and transpiration rates. Cladosporium cladosporioides was the dominant species on oat kernels in both experimental treatment options and in both years of the study. The presence of Fusarium poae was also found. Higher contents of prolamin, albumin and globulin fractions were found in the oat grain harvested from plants grown under soil water deficit conditions.

Downscaling near-surface soil moisture from field to plot scale: A comparative analysis under different environmental conditions

Science.gov (United States)

Nasta, Paolo; Penna, Daniele; Brocca, Luca; Zuecco, Giulia; Romano, Nunzio

2018-02-01

Indirect measurements of field-scale (hectometer grid-size) spatial-average near-surface soil moisture are becoming increasingly available by exploiting new-generation ground-based and satellite sensors. Nonetheless, modeling applications for water resources management require knowledge of plot-scale (1-5 m grid-size) soil moisture by using measurements through spatially-distributed sensor network systems. Since efforts to fulfill such requirements are not always possible due to time and budget constraints, alternative approaches are desirable. In this study, we explore the feasibility of determining spatial-average soil moisture and soil moisture patterns given the knowledge of long-term records of climate forcing data and topographic attributes. A downscaling approach is proposed that couples two different models: the Eco-Hydrological Bucket and Equilibrium Moisture from Topography. This approach helps identify the relative importance of two compound topographic indexes in explaining the spatial variation of soil moisture patterns, indicating valley- and hillslope-dependence controlled by lateral flow and radiative processes, respectively. The integrated model also detects temporal instability if the dominant type of topographic dependence changes with spatial-average soil moisture. Model application was carried out at three sites in different parts of Italy, each characterized by different environmental conditions. Prior calibration was performed by using sparse and sporadic soil moisture values measured by portable time domain reflectometry devices. Cross-site comparisons offer different interpretations in the explained spatial variation of soil moisture patterns, with time-invariant valley-dependence (site in northern Italy) and hillslope-dependence (site in southern Italy). The sources of soil moisture spatial variation at the site in central Italy are time-variant within the year and the seasonal change of topographic dependence can be conveniently

Soil moisture variations in remotely sensed and reanalysis datasets during weak monsoon conditions over central India and central Myanmar

Science.gov (United States)

Shrivastava, Sourabh; Kar, Sarat C.; Sharma, Anu Rani

2017-07-01

Variation of soil moisture during active and weak phases of summer monsoon JJAS (June, July, August, and September) is very important for sustenance of the crop and subsequent crop yield. As in situ observations of soil moisture are few or not available, researchers use data derived from remote sensing satellites or global reanalysis. This study documents the intercomparison of soil moisture from remotely sensed and reanalyses during dry spells within monsoon seasons in central India and central Myanmar. Soil moisture data from the European Space Agency (ESA)—Climate Change Initiative (CCI) has been treated as observed data and was compared against soil moisture data from the ECMWF reanalysis-Interim (ERA-I) and the climate forecast system reanalysis (CFSR) for the period of 2002-2011. The ESA soil moisture correlates rather well with observed gridded rainfall. The ESA data indicates that soil moisture increases over India from west to east and from north to south during monsoon season. The ERA-I overestimates the soil moisture over India, while the CFSR soil moisture agrees well with the remotely sensed observation (ESA). Over Myanmar, both the reanalysis overestimate soil moisture values and the ERA-I soil moisture does not show much variability from year to year. Day-to-day variations of soil moisture in central India and central Myanmar during weak monsoon conditions indicate that, because of the rainfall deficiency, the observed (ESA) and the CFSR soil moisture values are reduced up to 0.1 m3/m3 compared to climatological values of more than 0.35 m3/m3. This reduction is not seen in the ERA-I data. Therefore, soil moisture from the CFSR is closer to the ESA observed soil moisture than that from the ERA-I during weak phases of monsoon in the study region.

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.

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

Housing conditions affecting interior moisture levels: links to mould growth and children's respiratory health

Energy Technology Data Exchange (ETDEWEB)

Wells, John A. [Crosier Kilgour and Partners Ltd. (Canada)], email: john.w@ckpeng.com; Polyzois, Dimos [Department of Civil Engineering, University of Manitoba (Canada)], email: polyzoi@cc.umanitoba.ca; Polyzoi, Eleoussa [Faculty of Education, University of Winnipeg (Canada)], email: l.polyzoi@uwinnipeg.ca

2011-07-01

Previous research has demonstrated that a person's respiratory health is affected by high indoor moisture content in their house. The aim of this paper is to provide a better understanding of the link between housing conditions and respiratory health, so that strategies can be implemented to improve the quality of life of children. This study was carried out through the completion of a survey by 3,423 parents in Winnipeg, Canada, the collection of 715 air samples from the residences of 715 parents, and an engineering audit of their homes. This study showed that a strong relationship exists between building moisture content and common home maintenance and that routine maintenance is efficient in significantly reducing the growth of mould which impacts children's respiratory health. This paper provided useful information on the relation between housing conditions and respiratory health problems and the rest of the study will aim at determining which building conditions impact mould growth most.

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...

Effect of organic matter on the uptake of phosphorus by rice plants under different moisture conditions

International Nuclear Information System (INIS)

Ghosh, Geetanjali

1974-01-01

In studies on the effect of three levels of moisture and two levels of organic matter in two alluvial soils, the uptake of P by rice plant both from soil and fertilizer sources was the highest and Eh the lowest under submerged conditions. No marked difference in total uptake of P was observed in upland and alternate submerged condition; organic matter application showed an appreciable effect under submerged condition. (author)

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.

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...

Role of soil moisture versus recent climate change for the 2010 heat wave in western Russia

Science.gov (United States)

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

2016-03-01

The severe 2010 heat wave in western Russia was found to be influenced by anthropogenic climate change. Additionally, soil moisture-temperature feedbacks were deemed important for the buildup of the exceptionally high temperatures. We quantify the relative role of both factors by applying the probabilistic event attribution framework and analyze ensemble simulations to distinguish the effect of climate change and the 2010 soil moisture conditions for annual maximum temperatures. The dry 2010 soil moisture alone has increased the risk of a severe heat wave in western Russia sixfold, while climate change from 1960 to 2000 has approximately tripled it. The combined effect of climate change and 2010 soil moisture yields a 13 times higher heat wave risk. We conclude that internal climate variability causing the dry 2010 soil moisture conditions formed a necessary basis for the extreme heat wave.

Magnetic susceptibility and magnetic resonance measurements of the moisture content and hydration condition of a magnetic mixture material

International Nuclear Information System (INIS)

Tsukada, K.; Kusaka, T.; Saari, M. M.; Takagi, R.; Sakai, K.; Kiwa, T.; Bito, Y.

2014-01-01

We developed a magnetic measurement method to measure the moisture content and hydration condition of mortar as a magnetic mixture material. Mortar is a mixture of Portland cement, sand, and water, and these materials exhibit different magnetic properties. The magnetization–magnetic field curves of these components and of mortars with different moisture contents were measured, using a specially developed high-temperature-superconductor superconducting quantum interference device. Using the differences in magnetic characteristics, the moisture content of mortar was measured at the ferromagnetic saturation region over 250 mT. A correlation between magnetic susceptibility and moisture content was successfully established. After Portland cement and water are mixed, hydration begins. At the early stage of the hydration/gel, magnetization strength increased over time. To investigate the magnetization change, we measured the distribution between bound and free water in the mortar in the early stage by magnetic resonance imaging (MRI). The MRI results suggest that the amount of free water in mortar correlates with the change in magnetic susceptibility

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.)

Effect of moisture content and storage conditions on the storability of ...

African Journals Online (AJOL)

STORAGESEVER

2008-12-17

Dec 17, 2008 ... Rhizopus sp. were more abundant with increasing moisture content. Air-tight .... jute bag. The aim of this study is to evaluate the role of moisture and storage .... be due to contamination as a result of local method of processing.

Assessing Vegetation Response to Soil Moisture Fluctuation under Extreme Drought Using Sentinel-2

Directory of Open Access Journals (Sweden)

Harry West

2018-06-01

Full Text Available The aim of this study was to determine the extent to which Sentinel-2 Normalised Difference Vegetation Index (NDVI reflects soil moisture conditions, and whether this product offers an improvement over Landsat-8. Based on drought exposure, cloud-free imagery availability, and measured soil moisture, five sites in the Southwestern United States were selected. These sites, normally dry to arid, were in various states of drought. A secondary focus was therefore the performance of the NDVI under extreme conditions. Following supervised classification, the NDVI values for one-kilometre radius areas were calculated. Sentinel-2 NDVI variants using Spectral Bands 8 (10 m spatial resolution, 5, 6, 7, and 8A (20 m spatial resolution were calculated. Landsat-8 NDVI was calculated at 30 m spatial resolution. Pearson correlation analysis was undertaken for NDVI against moisture at various depths. To assess the difference in correlation strength, a principal component analysis was performed on the combination of all bands and the combination of the new red-edge bands. Performance of the red-edge NDVI against the standard near infrared (NIR was then evaluated using a Steiger comparison. No significant correlations between Landsat-8 NDVI and soil moisture were found. Significant correlations at depths of less than 30 cm were present between Sentinel-2 NDVI and soil moisture at three sites. The remaining two sites were characterised by low vegetation cover, suggesting a cover threshold of approximately 30–40% is required for a correlation to be present. At all sites of significant positive moisture to NDVI correlation, the linear combination of the red-edge bands produced stronger correlations than the poorer spectral but higher spatial resolution band. NDVI calculated using the higher spectral resolution bands may therefore be of greater use in this context than the higher spatial resolution option. Results suggest potential for the application of Sentinel-2

Spring soil moisture-precipitation feedback in the Southern Great Plains: How is it related to large-scale atmospheric conditions?

KAUST Repository

Su, Hua

2014-02-22

The Southern Great Plains (SGP) has been shown as a region of significant soil moisture-precipitation (S-P) coupling. However, how strong evapotranspiration (ET) can affect regional precipitation remains largely unclear, impeding a full grasp of the S-P feedback in that area. The current study seeks to unravel, in a spring month (April), the potential role played by large-scale atmospheric conditions in shaping S (ET)-P feedback. Our regional climate modeling experiments demonstrate that the presence of anomalous low (high) pressure and cyclonic (anticyclonic) flows at the upper/middle troposphere over the relevant areas is associated with strongest (minimum) positive S-P feedback in the SGP. Their impacts are interpreted in terms of large-scale atmospheric dynamical disturbance, including the intensity and location of synoptic eddies. Further analyses of the vertical velocity fields corroborate these interpretations. In addition, the relationship between lower tropospheric moisture conditions (including winds) and feedback composites is evaluated. Key Points The S-P feedback strength in SGP in April varies inter-annually The atmospheric dynamic features affect significantly the feedback strength composite moisture conditions are related to atmospheric circulation structure ©2014. American Geophysical Union. All Rights Reserved.

Spring soil moisture-precipitation feedback in the Southern Great Plains: How is it related to large-scale atmospheric conditions?

KAUST Repository

Su, Hua; Yang, Zong-Liang; Dickinson, Robert E.; Wei, Jiangfeng

2014-01-01

The Southern Great Plains (SGP) has been shown as a region of significant soil moisture-precipitation (S-P) coupling. However, how strong evapotranspiration (ET) can affect regional precipitation remains largely unclear, impeding a full grasp of the S-P feedback in that area. The current study seeks to unravel, in a spring month (April), the potential role played by large-scale atmospheric conditions in shaping S (ET)-P feedback. Our regional climate modeling experiments demonstrate that the presence of anomalous low (high) pressure and cyclonic (anticyclonic) flows at the upper/middle troposphere over the relevant areas is associated with strongest (minimum) positive S-P feedback in the SGP. Their impacts are interpreted in terms of large-scale atmospheric dynamical disturbance, including the intensity and location of synoptic eddies. Further analyses of the vertical velocity fields corroborate these interpretations. In addition, the relationship between lower tropospheric moisture conditions (including winds) and feedback composites is evaluated. Key Points The S-P feedback strength in SGP in April varies inter-annually The atmospheric dynamic features affect significantly the feedback strength composite moisture conditions are related to atmospheric circulation structure ©2014. American Geophysical Union. All Rights Reserved.

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...

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...

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.

Forest litter crickets prefer higher substrate moisture for oviposition: Evidence from field and lab experiments.

Science.gov (United States)

de Farias-Martins, Fernando; Sperber, Carlos Frankl; Albeny-Simões, Daniel; Breaux, Jennifer Ann; Fianco, Marcos; Szinwelski, Neucir

2017-01-01

For insects, choosing a favorable oviposition site is a type of parental care, as far as it increases the fitness of its offspring. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate moisture. However, lab experiments with mole crickets showed a linear oviposition response to substrate moisture. Studies with the house cricket Acheta domesticus also showed a linear juvenile body growth response to water availability, thus adult ovipositing females should respond positively to substrate moisture. We used a field experiment to evaluate the relationship between oviposition preference and substrate moisture in forest litter-dwelling cricket species. We also evaluated oviposition responses to substrate moisture level in Ubiquepuella telytokous, the most abundant litter cricket species in our study area, using a laboratory study. We offered cotton substrate for oviposition which varied in substrate moisture level from zero (i.e., dry) to maximum water absorption capacity. We used two complementary metrics to evaluate oviposition preference: (i) presence or absence of eggs in each sampling unit as binary response variable, and (ii) number of eggs oviposited per sampling unit as count response variable. To test for non-linear responses, we adjusted generalized additive models (GAMM) with mixed effects. We found that both cricket oviposition probability and effort (i.e., number of eggs laid) increased linearly with substrate moisture in the field experiment, and for U. telytokous in the lab experiment. We discarded any non-linear responses. Our results demonstrate the importance of substrate moisture as an ecological niche dimension for litter crickets. This work bolsters knowledge of litter cricket life history association with moisture, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying.

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

FINAL REPORT FOR MOISTURE EFFECTS ON COMPACTION OF FIBERBOARD IN A 9975 SHIPPING PACKAGE

Energy Technology Data Exchange (ETDEWEB)

Stefek, T.; Daugherty, W.; Estochen, E.

2013-09-17

Compaction of lower layers in the fiberboard assembly has been observed in 9975 packages that contain elevated moisture. Lab testing has resulted in a better understanding of the relationship between the fiberboard moisture level and compaction of the lower fiberboard assembly, and the behavior of the fiberboard during transport. In laboratory tests of cane fiberboard, higher moisture content has been shown to correspond to higher total compaction, greater rate of compaction, and continued compaction over a longer period of time. In addition, laboratory tests have shown that the application of a dynamic load results in higher fiberboard compaction compared to a static load. The test conditions and sample geometric/loading configurations were chosen to simulate the regulatory requirements for 9975 package input dynamic loading. Dynamic testing was conducted to acquire immediate and cumulative changes in geometric data for various moisture levels. Two sample sets have undergone a complete dynamic test regimen, one set for 27 weeks, and the second set for 47 weeks. The dynamic input, data acquisition, test effects on sample dynamic parameters, and results from this test program are summarized and compared to regulatory specifications for dynamic loading. Compaction of the bottom fiberboard layers due to the accumulation of moisture is one possible cause of an increase in the axial gap at the top of the package. The net compaction of the bottom layers will directly add to the axial gap. The moisture which caused this compaction migrated from the middle region of the fiberboard assembly (which is typically the hottest). This will cause the middle region to shrink axially, which will also contribute directly to the axial gap. Measurement of the axial gap provides a screening tool for identifying significant change in the fiberboard condition. The data in this report provide a basis to evaluate the impact of moisture and fiberboard compaction on 9975 package performance

Agronomic response of cultivars of chickpea (Cicer arietinum L. under different soil moisture conditions in province Granma

Directory of Open Access Journals (Sweden)

Yanitza Meriño Hernández

2017-07-01

Full Text Available To objective of evaluate the response of two cultivars of chickpea (Nac-29 and Nac-5 HA under different soil moisture conditions, field research was carried out in productive teaching plot of the University of Granma. Sowing was carried out on November 22, 2014. Two treatments were used: T1 (Control and T2 (varieties of chickpea in water stress with three replicates, distributed in a randomized block design with split plot arrangements (The large plots corresponded to the two moisture conditions and the small plots to varieties. The variables were: length and diameter of pods, number of grains per plant, number of grains per pods, weight of 100 seeds and agricultural yield. The results obtained were statistically processed using the STATISTICA version 8.0 for Windows program and in case of significant differences, a variance analysis was performed using the Tukey Multiple Range test. The results showed that, with the cultivation of the chickpea, better results are obtained when the plants are subjected to water stress conditions.

Diuron mineralisation in a Mediterranean vineyard soil: impact of moisture content and temperature.

Science.gov (United States)

El Sebaï, Talaat; Devers, Marion; Lagacherie, Bernard; Rouard, Nadine; Soulas, Guy; Martin-Laurent, Fabrice

2010-09-01

The diuron-mineralising ability of the microbiota of a Mediterranean vineyard soil exposed each year to this herbicide was measured. The impact of soil moisture and temperature on this microbial activity was assessed. The soil microbiota was shown to mineralise diuron. This mineralising activity was positively correlated with soil moisture content, being negligible at 5% and more than 30% at 20% soil moisture content. According to a double Gaussian model applied to fit the dataset, the optimum temperature/soil moisture conditions were 27.9 degrees C/19.3% for maximum mineralisation rate and 21.9 degrees C/18.3% for maximum percentage mineralisation. The impact of temperature and soil moisture content variations on diuron mineralisation was estimated. A simulated drought period had a suppressive effect on subsequent diuron mineralisation. This drought effect was more marked when higher temperatures were used to dry (40 degrees C versus 28 degrees C) or incubate (28 degrees C versus 20 degrees C) the soil. The diuron kinetic parameters measured after drought conditions were no longer in accordance with those estimated by the Gaussian model. Although soil microbiota can adapt to diuron mineralisation, its activity is strongly dependent on climatic conditions. It suggests that diuron is not rapidly degraded under Mediterranean climate, and that arable Mediterranean soils are likely to accumulate diuron residues. (c) 2010 Society of Chemical Industry.

Role of Soil Moisture vs. Recent Climate Change for the 2010 Heat Wave in Western Russia

Science.gov (United States)

Hauser, Mathias; Orth, René; Seneviratne, Sonia

2016-04-01

Extreme event attribution statements are often conditional on increased greenhouse gas concentrations or a particular ocean state, but not on other physical factors of the climate system. Here we extend the classical framework and assess the influence of soil moisture on a heat wave to obtain a physical attribution statement. In particular, we test the role of soil-moisture-temperature feedbacks which have been shown to be generally relevant for the build-up of exceptionally high temperatures. As a case study we investigate the severe 2010 heat wave in western Russia, which was previously found to be influenced by anthropogenic climate change. We quantify the relative role of climate change and that of soil moisture-temperature feedbacks with the event attribution framework and analyze ensemble simulations to distinguish the effect of climate change and the 2010 soil moisture conditions for annual maximum temperatures. We find that climate change from 1960 to 2000 alone has approximately tripled the risk of a severe heat wave in western Russia. The combined effect of climate change and the dry 2010 soil moisture yields a 13 times higher heat wave risk. We conclude that internal climate variability causing the dry 2010 soil moisture conditions formed the basis for this extreme heatwave.

Variation in root activity with season and soil moisture in coconut

International Nuclear Information System (INIS)

Venugopal, Vandana; Balachandran, P.V.

2007-01-01

An experiment was conducted at the College of Horticulture, Vellanikkara to study the effect of season and soil moisture regime on the physiological activity of roots in coconut. The experiment has been laid out in CRD with two replications at two different depths (20 and 75 cm) and moisture regimes (irrigated and rain fed) round the year. The 32 P uptake was higher during wet season as compared to dry season in monocrop of coconut. The absorption was more from the surface layers during wet season and roots explored deeper soil layers during dry season. Irrigation in general improved absorption of 32 P in coconut and resulted in higher uptake from the surface soil compared to that under rainfed condition. (author)

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

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...

Can crawl space temperature and moisture conditions be calculated with a whole-building hygrothermal simulation tool?

DEFF Research Database (Denmark)

Vanhoutteghem, Lies; Morelli, Martin; Sørensen, Lars Schiøtt

2017-01-01

of measurements was compared with simulations of temperature and moisture condition in the floor structure and crawl space. The measurements showed that the extra 50 mm insulation placed below the beams reduced moisture content in the beams below 20 weight% all year. A reasonable agreement between......The hygrothermal behaviour of an outdoor ventilated crawl space with two different designs of the floor structure was investigated. The first design had 250 mm insulation and visible wooden beams towards the crawl space. The second design had 300 mm insulation and no visible wooden beams. One year...... the measurements and simulations was found; however, the evaporation from the soil was a dominant parameter affecting the hygrothermal response in the crawl space and floor structure....

Attribution of soil moisture dynamics - Initial conditions vs. atmospheric forcing and the role of climate change

Science.gov (United States)

Orth, Rene; Seneviratne, Sonia I.

2014-05-01

conditions versus the atmospheric forcing for monthly soil moisture variations. We find that initial soil moisture anomalies are overall more important than the forcing, even if less pronounced in summer. Especially in southern Europe we show high drought forecasting potential, whereas the forcing is more important in Central and North-eastern Europe.

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...

STATUS REPORT FOR MOISTURE EFFECTS ON COMPACTION OF FIBERBOARD IN A 9975 SHIPPING PACKAGE

Energy Technology Data Exchange (ETDEWEB)

Stefek, T.; Daugherty, W.; Estochen, E.

2011-06-23

Compaction of lower layers in the fiberboard overpack has been observed in 9975 packages that contain elevated moisture. Lab testing has resulted in a better understanding of the relationship between the fiberboard moisture level and compaction of the lower fiberboard assembly, and the behavior of the fiberboard during transport. In laboratory tests, higher moisture content has been shown to correspond to higher total compaction of fiberboard material, greater rate of compaction, and continued compaction over a longer period of time. In addition, laboratory tests have shown that the application of a dynamic load results in higher fiberboard compaction. The test conditions and sample geometric/loading configurations were chosen to simulate the regulatory requirements for 9975 package input dynamic loading. Dynamic testing was conducted over a period of six months to acquire immediate and cumulative changes in geometric data for various moisture levels. Currently, one sample set has undergone a complete dynamic test regimen, while testing of another set is still in-progress. The dynamic input, data acquisition, test effects on sample dynamic parameters, and interim results from this test program are summarized and compared to regulatory specifications for dynamic loading. This will provide a basis from which to evaluate the impact of moisture and fiberboard compaction on the safety basis for transportation (Safety Analysis Report for Packaging) and storage (facility Documented Safety Analysis) at the Savannah River Site (SRS).

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.

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)

Moisture rivals temperature in limiting photosynthesis by trees establishing beyond their cold-edge range limit under ambient and warmed conditions.

Science.gov (United States)

Moyes, Andrew B; Germino, Matthew J; Kueppers, Lara M

2015-09-01

Climate change is altering plant species distributions globally, and warming is expected to promote uphill shifts in mountain trees. However, at many cold-edge range limits, such as alpine treelines in the western United States, tree establishment may be colimited by low temperature and low moisture, making recruitment patterns with warming difficult to predict. We measured response functions linking carbon (C) assimilation and temperature- and moisture-related microclimatic factors for limber pine (Pinus flexilis) seedlings growing in a heating × watering experiment within and above the alpine treeline. We then extrapolated these response functions using observed microclimate conditions to estimate the net effects of warming and associated soil drying on C assimilation across an entire growing season. Moisture and temperature limitations were each estimated to reduce potential growing season C gain from a theoretical upper limit by 15-30% (c. 50% combined). Warming above current treeline conditions provided relatively little benefit to modeled net assimilation, whereas assimilation was sensitive to either wetter or drier conditions. Summer precipitation may be at least as important as temperature in constraining C gain by establishing subalpine trees at and above current alpine treelines as seasonally dry subalpine and alpine ecosystems continue to warm. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Production of starch nanoparticles using normal maize starch via heat-moisture treatment under mildly acidic conditions and homogenization.

Science.gov (United States)

Park, Eun Young; Kim, Min-Jung; Cho, MyoungLae; Lee, Ju Hun; Kim, Jong-Yea

2016-10-20

Normal maize starch was subjected to heat-moisture treatment (HMT) under mildly acidic conditions (0.000, 0.050, or 0.075M H2SO4) for various treatment times (3, 5, or 8h) followed by homogenization up to 60min to prepare nanoparticles. The combination of HMT (0.075M, for 8h) and homogenization (60min) produced nanoparticles with diameters of less than 50nm at a yield higher than 80%. X-ray diffractometry and size-exclusion chromatography revealed that HMT under mildly acidic conditions selectively hydrolyzed the starch chains (especially amylose and/or long chains of amylopectin) in the amorphous region of the granules without significant damage to the crystalline structure, however, modification of the molecular structure in the amorphous region increased fragility of the granules during homogenization. Homogenization for 60min caused obvious damage in the long-range crystalline structure of the HMT starch (0.15N, for 8h), while the short-range chain associations (FT-IR) remained intact. Copyright © 2016 Elsevier Ltd. All rights reserved.

Resistant Starch Contents of Native and Heat-Moisture Treated Jackfruit Seed Starch

Directory of Open Access Journals (Sweden)

Ornanong S. Kittipongpatana

2015-01-01

Full Text Available Native jackfruit seed starch (JFS contains 30% w/w type II resistant starch (RS2 and can potentially be developed as a new commercial source of RS for food and pharmaceutical application. Heat-moisture treatment (HMT was explored as a mean to increase RS content of native JFS. The effect of the conditions was tested at varied moisture contents (MC, temperatures, and times. Moisture levels of 20–25%, together with temperatures 80–110°C, generally resulted in increases of RS amount. The highest amount of RS (52.2% was achieved under treatment conditions of 25% MC and 80°C, for 16 h (JF-25-80-16. FT-IR peak ratio at 1047/1022 cm−1 suggested increases in ordered structure in several HMT-JFS samples with increased RS. SEM showed no significant change in the granule appearance, except at high moisture/temperature treatment. XRD revealed no significant change in peaks intensities, suggesting the crystallinity within the granule was mostly retained. DSC showed increases in Tg and, in most cases, ΔT, as the MC was increased in the samples. Slight but significant decreases in ΔH were observed in samples with low RS, indicating that a combination of high moisture and temperature might cause partial gelatinization. HMT-JFS with higher RS exhibited less swelling, while the solubility remained mostly unchanged.

Effect of Moisture Content of Chitin-Calcium Silicate on Rate of Degradation of Cefotaxime Sodium.

Science.gov (United States)

Al-Nimry, Suhair S; Alkhamis, Khouloud A

2018-04-01

Assessment of incompatibilities between active pharmaceutical ingredient and pharmaceutical excipients is an important part of preformulation studies. The objective of the work was to assess the effect of moisture content of chitin calcium silicate of two size ranges (two specific surface areas) on the rate of degradation of cefotaxime sodium. The surface area of the excipient was determined using adsorption method. The effect of moisture content of a given size range on the stability of the drug was determined at 40°C in the solid state. The moisture content was determined at the beginning and the end of the kinetic study using TGA. The degradation in solution was studied for comparison. Increasing the moisture content of the excipient of size range 63-180 μm (surface area 7.2 m 2 /g) from 3.88 to 8.06% increased the rate of degradation of the drug more than two times (from 0.0317 to 0.0718 h -1 ). While an opposite trend was observed for the excipient of size range moisture content moisture content of 8.54%, and the degradation in solid state at both moisture contents was higher than that in solution (0.0871 h -1 ). In conclusion, the rate of degradation in solid should be studied taking into consideration the specific surface area and moisture content of the excipient at the storage condition and it may be higher than that in solution.

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

Effects of climate change on soil moisture over China from 1960-2006

Science.gov (United States)

Zhu, Q.; Jiang, H.; Liu, J.

2009-01-01

Soil moisture is an important variable in the climate system and it has sensitive impact on the global climate. Obviously it is one of essential components in the climate change study. The Integrated Biosphere Simulator (IBIS) is used to evaluate the spatial and temporal patterns of soil moisture across China under the climate change conditions for the period 1960-2006. Results show that the model performed better in warm season than in cold season. Mean errors (ME) are within 10% for all the months and root mean squared errors (RMSE) are within 10% except winter season. The model captured the spatial variability higher than 50% in warm seasons. Trend analysis based on the Mann-Kendall method indicated that soil moisture in most area of China is decreased especially in the northern China. The areas with significant increasing trends in soil moisture mainly locate at northwestern China and small areas in southeastern China and eastern Tibet plateau. ?? 2009 IEEE.

Impact of soil moisture initialization on boreal summer subseasonal forecasts: mid-latitude surface air temperature and heat wave events

Science.gov (United States)

Seo, Eunkyo; Lee, Myong-In; Jeong, Jee-Hoon; Koster, Randal D.; Schubert, Siegfried D.; Kim, Hye-Mi; Kim, Daehyun; Kang, Hyun-Suk; Kim, Hyun-Kyung; MacLachlan, Craig; Scaife, Adam A.

2018-05-01

This study uses a global land-atmosphere coupled model, the land-atmosphere component of the Global Seasonal Forecast System version 5, to quantify the degree to which soil moisture initialization could potentially enhance boreal summer surface air temperature forecast skill. Two sets of hindcast experiments are performed by prescribing the observed sea surface temperature as the boundary condition for a 15-year period (1996-2010). In one set of the hindcast experiments (noINIT), the initial soil moisture conditions are randomly taken from a long-term simulation. In the other set (INIT), the initial soil moisture conditions are taken from an observation-driven offline Land Surface Model (LSM) simulation. The soil moisture conditions from the offline LSM simulation are calibrated using the forecast model statistics to minimize the inconsistency between the LSM and the land-atmosphere coupled model in their mean and variability. Results show a higher boreal summer surface air temperature prediction skill in INIT than in noINIT, demonstrating the potential benefit from an accurate soil moisture initialization. The forecast skill enhancement appears especially in the areas in which the evaporative fraction—the ratio of surface latent heat flux to net surface incoming radiation—is sensitive to soil moisture amount. These areas lie in the transitional regime between humid and arid climates. Examination of the extreme 2003 European and 2010 Russian heat wave events reveal that the regionally anomalous soil moisture conditions during the events played an important role in maintaining the stationary circulation anomalies, especially those near the surface.

Detecting the honeycomb sandwich composite material's moisture impregnating defects by using infrared thermography technique

International Nuclear Information System (INIS)

Kwon, Koo Ahn; Choi, Man Yong; Park, Jeong Hak; Choi, Won Jae; Park, Hee Sang

2017-01-01

Many composite materials are used in the aerospace industry because of their excellent mechanical properties. However, the nature of aviation exposes these materials to high temperature and high moisture conditions depending on climate, location, and altitude. Therefore, the molecular arrangement chemical properties, and mechanical properties of composite materials can be changed under these conditions. As a result, surface disruptions and cracks can be created. Consequently, moisture-impregnating defects can be induced due to the crack and delamination of composite materials as they are repeatedly exposed to moisture absorption moisture release, fatigue environment, temperature changes, and fluid pressure changes. This study evaluates the possibility of detecting the moisture-impregnating defects of CFRP and GFRP honeycomb structure sandwich composite materials, which are the composite materials in the aircraft structure, by using an active infrared thermography technology among non-destructive testing methods. In all experiments, it was possible to distinguish the area and a number of CFRP composite materials more clearly than those of GFRP composite material. The highest detection rate was observed in the heating duration of 50 mHz and the low detection rate was at the heating duration of over 500 mHz. The reflection method showed a higher detection rate than the transmission method

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...

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

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)

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

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.

Detecting Trends in Wetland Extent from MODIS Derived Soil Moisture Estimates

Directory of Open Access Journals (Sweden)

Thomas Gumbricht

2018-04-01

Full Text Available A soil wetness index for optical satellite images, the Transformed Wetness Index (TWI is defined and evaluated against ground sampled soil moisture. Conceptually, TWI is formulated as a non-linear normalized difference index from orthogonalized vectors representing soil and water conditions, with the vegetation signal removed. Compared to 745 ground sites with in situ measured soil moisture, TWI has a globally estimated Random Mean Square Error of 14.0 (v/v expressed as percentage, which reduces to 8.5 for unbiased data. The temporal variation in soil moisture is significantly captured at 4 out of 10 stations, but also fails for 2 to 3 out of 10 stations. TWI is biased by different soil mineral compositions, dense vegetation and shadows, with the latter two most likely also causing the failure of TWI to capture soil moisture dynamics. Compared to soil moisture products from microwave brightness temperature data, TWI performs slightly worse, but has the advantages of not requiring ancillary data, higher spatial resolution and a relatively simple application. TWI has been used for wetland and peatland mapping in previously published studies but is presented in detail in this article, and then applied for detecting changes in soil moisture for selected tropical regions between 2001 and 2016. Sites with significant changes are compared to a published map of global tropical wetlands and peatlands.

Thermal shock effect on Mechanical and Physical properties of pre-moisture treated GRE composite

Science.gov (United States)

Chakraverty, A. P.; Panda, A. B.; Mohanty, U. K.; Mishra, S. C.; Biswal, B. B.

2018-03-01

Many practical situations may be encountered under which a GFRP (Glass fibre reinforced polymer) composite, during its service life, is exposed to the severities of sudden temperature fluctuations. Moisture absorption of GRE (Glass fibre reinforced epoxy) composites followed by various gradients of temperature fluctuations may cause thermo- mechanical degradation. It is on this context, the hand layed GRE composite samples are exposed to up-thermal shock (-40°C to +50°C) and down-thermal shock (+50°C to -40°C) for various time interval after several periods of moisture (hydrothermal/hygrothermal) conditioning. The thermally shocked GRE specimens are put to 3-point bend test to divulge inter laminar shear strength (ILSS). Least ILSS values are recorded for the samples with maximum period of moisture treatments under with both up-thermal and down-thermal shock conditions. Lower glass transition temperature (Tg) values, as revealed through the low temperature DSC test, are exhibited at maximum durations of both up-thermal and down-thermal shock for the samples with higher periods of hygrothermal/hydrothermal treatments. SEM fractographs of representative GRE specimens after optimum period of moisture treatments and thermal shock show the various modes of failures.

Effect of moisture content on fed batch composting reactor of vegetable and fruit wastes.

Science.gov (United States)

Jolanun, B; Tripetchkul, S; Chiemchaisri, C; Chaiprasert, P; Towprayoon, S

2005-03-01

Vegetable and fruit wastes mixed with sawdust were composted in a laboratory scale reactor by controlling the waste feeding rate at 21 kg m(-3) day(-1) and aeration rate at 10.6 l m(-3) min(-1). The effects of initial moisture content on organic matter degradation and process performance of fed batch composting were investigated. The absolute amount of removal, removal percentage, and removal rate of dry mass obtained were substantially different among the initial moisture contents. The rapid rise of moisture content and the lowest absolute amount of removal observed were achieved in the 50% condition. The initial moisture content yielding the largest absolute amount of removal in both feeding and curing stage was 30% whereas the removal percentage and rate constant of waste decomposition were highest in the 50% condition. Examined by traditional soil physics method, the moisture content at 50-55% was suitable for satisfying the degree of free air space (65-70%) of compost during the fed batch composting. Most degradable organic matter was mainly consumed in the feeding stage as indicated by a higher removal rate of dry mass in all cases. It is recommended that the initial moisture content of 30% and mode of aeration and agitation should be adopted for achieving practical fed batch composting of vegetable and fruit wastes. The study also demonstrated that the composting kinetics of vegetable and fruit wastes mixed with sawdust can be described by a first order model.

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...

Estimating the responses of winter wheat yields to moisture variations in the past 35 years in Jiangsu Province of China.

Science.gov (United States)

Xu, Xiangying; Gao, Ping; Zhu, Xinkai; Guo, Wenshan; Ding, Jinfeng; Li, Chunyan

2018-01-01

Jiangsu is an important agricultural province in China. Winter wheat, as the second major grain crop in the province, is greatly affected by moisture variations. The objective of this study was to investigate whether there were significant trends in changes in the moisture conditions during wheat growing seasons over the past decades and how the wheat yields responded to different moisture levels by means of a popular drought index, the Standardized Precipitation Evapotranspiration Index (SPEI). The study started with a trend analysis and quantification of the moisture conditions with the Mann-Kendall test and Sen's Slope method, respectively. Then, correlation analysis was carried out to determine the relationship between de-trended wheat yields and multi-scalar SPEI. Finally, a multivariate panel regression model was established to reveal the quantitative yield responses to moisture variations. The results showed that the moisture conditions in Jiangsu were generally at a normal level, but this century appeared slightly drier in because of the relatively high temperatures. There was a significant correlation between short time scale SPEI values and wheat yields. Among the three critical stages of wheat development, the SPEI values in the late growth stage (April-June) had a closer linkage to the yields than in the seedling stage (October-November) and the over-wintering stage (December-February). Moreover, the yield responses displayed an asymmetric characteristic, namely, moisture excess led to higher yield losses compared to moisture deficit in this region. The maximum yield increment could be obtained under the moisture level of slight drought according to the 3-month SPEI at the late growth stage, while extreme wetting resulted in the most severe yield losses. The moisture conditions in the first 15 years of the 21st century were more favorable than in the last 20 years of the 20th century for wheat production in Jiangsu.

Estimating the responses of winter wheat yields to moisture variations in the past 35 years in Jiangsu Province of China.

Directory of Open Access Journals (Sweden)

Xiangying Xu

Full Text Available Jiangsu is an important agricultural province in China. Winter wheat, as the second major grain crop in the province, is greatly affected by moisture variations. The objective of this study was to investigate whether there were significant trends in changes in the moisture conditions during wheat growing seasons over the past decades and how the wheat yields responded to different moisture levels by means of a popular drought index, the Standardized Precipitation Evapotranspiration Index (SPEI. The study started with a trend analysis and quantification of the moisture conditions with the Mann-Kendall test and Sen's Slope method, respectively. Then, correlation analysis was carried out to determine the relationship between de-trended wheat yields and multi-scalar SPEI. Finally, a multivariate panel regression model was established to reveal the quantitative yield responses to moisture variations. The results showed that the moisture conditions in Jiangsu were generally at a normal level, but this century appeared slightly drier in because of the relatively high temperatures. There was a significant correlation between short time scale SPEI values and wheat yields. Among the three critical stages of wheat development, the SPEI values in the late growth stage (April-June had a closer linkage to the yields than in the seedling stage (October-November and the over-wintering stage (December-February. Moreover, the yield responses displayed an asymmetric characteristic, namely, moisture excess led to higher yield losses compared to moisture deficit in this region. The maximum yield increment could be obtained under the moisture level of slight drought according to the 3-month SPEI at the late growth stage, while extreme wetting resulted in the most severe yield losses. The moisture conditions in the first 15 years of the 21st century were more favorable than in the last 20 years of the 20th century for wheat production in Jiangsu.

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...

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...

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.

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

[Response processes of Aralia elata photosynthesis and transpiration to light and soil moisture].

Science.gov (United States)

Chen, Jian; Zhang, Guang-Can; Zhang, Shu-Yong; Wang, Meng-Jun

2008-06-01

By using CIRAS-2 portable photosynthesis system, the light response processes of Aralia elata photosynthesis and transpiration under different soil moisture conditions were studied, aimed to understand the adaptability of A. elata to different light and soil moisture conditions. The results showed that the response processes of A. elata net photosynthetic rate (Pn), transpiration rate (Tr), and water use efficiency (WUE) to photon flux density (PFD) were different. With the increasing PFD in the range of 800-1800 micromol x m2(-2) x s(-1), Pn changed less, Tr decreased gradually, while WUE increased obviously. The light saturation point (LSP) and light compensation point (LCP) were about 800 and 30 micromol m(-2) x s(-1), respectively, and less affected by soil water content; while the apparent photosynthetic quantum yield (Phi) and dark respiratory rate (Rd) were more affected by the moisture content. The Pn and WUE had evident threshold responses to the variations of soil water content. When the soil relative water content (RWC) was in the range of 44%-79%, A. elata could have higher levels of Pn and WUE.

Impact of soil moisture on extreme maximum temperatures in Europe

Directory of Open Access Journals (Sweden)

Kirien Whan

2015-09-01

Full Text Available Land-atmosphere interactions play an important role for hot temperature extremes in Europe. Dry soils may amplify such extremes through feedbacks with evapotranspiration. While previous observational studies generally focused on the relationship between precipitation deficits and the number of hot days, we investigate here the influence of soil moisture (SM on summer monthly maximum temperatures (TXx using water balance model-based SM estimates (driven with observations and temperature observations. Generalized extreme value distributions are fitted to TXx using SM as a covariate. We identify a negative relationship between SM and TXx, whereby a 100 mm decrease in model-based SM is associated with a 1.6 °C increase in TXx in Southern-Central and Southeastern Europe. Dry SM conditions result in a 2–4 °C increase in the 20-year return value of TXx compared to wet conditions in these two regions. In contrast with SM impacts on the number of hot days (NHD, where low and high surface-moisture conditions lead to different variability, we find a mostly linear dependency of the 20-year return value on surface-moisture conditions. We attribute this difference to the non-linear relationship between TXx and NHD that stems from the threshold-based calculation of NHD. Furthermore the employed SM data and the Standardized Precipitation Index (SPI are only weakly correlated in the investigated regions, highlighting the importance of evapotranspiration and runoff for resulting SM. Finally, in a case study for the hot 2003 summer we illustrate that if 2003 spring conditions in Southern-Central Europe had been as dry as in the more recent 2011 event, temperature extremes in summer would have been higher by about 1 °C, further enhancing the already extreme conditions which prevailed in that year.

Effects of Soil Moisture on the Temperature Sensitivity of Soil Heterotrophic Respiration: A Laboratory Incubation Study

Science.gov (United States)

Zhou, Weiping; Hui, Dafeng; Shen, Weijun

2014-01-01

The temperature sensitivity (Q10) of soil heterotrophic respiration (Rh) is an important ecological model parameter and may vary with temperature and moisture. While Q10 generally decreases with increasing temperature, the moisture effects on Q10 have been controversial. To address this, we conducted a 90-day laboratory incubation experiment using a subtropical forest soil with a full factorial combination of five moisture levels (20%, 40%, 60%, 80%, and 100% water holding capacity - WHC) and five temperature levels (10, 17, 24, 31, and 38°C). Under each moisture treatment, Rh was measured several times for each temperature treatment to derive Q10 based on the exponential relationships between Rh and temperature. Microbial biomass carbon (MBC), microbial community structure and soil nutrients were also measured several times to detect their potential contributions to the moisture-induced Q10 variation. We found that Q10 was significantly lower at lower moisture levels (60%, 40% and 20% WHC) than at higher moisture level (80% WHC) during the early stage of the incubation, but became significantly higher at 20%WHC than at 60% WHC and not significantly different from the other three moisture levels during the late stage of incubation. In contrast, soil Rh had the highest value at 60% WHC and the lowest at 20% WHC throughout the whole incubation period. Variations of Q10 were significantly associated with MBC during the early stages of incubation, but with the fungi-to-bacteria ratio during the later stages, suggesting that changes in microbial biomass and community structure are related to the moisture-induced Q10 changes. This study implies that global warming’s impacts on soil CO2 emission may depend upon soil moisture conditions. With the same temperature rise, wetter soils may emit more CO2 into the atmosphere via heterotrophic respiration. PMID:24647610

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.

Detecting the honeycomb sandwich composite material's moisture impregnating defects by using infrared thermography technique

Energy Technology Data Exchange (ETDEWEB)

Kwon, Koo Ahn; Choi, Man Yong; Park, Jeong Hak; Choi, Won Jae [Safety Measurement Center, Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Park, Hee Sang [R and D, Korea Research Institute of Smart Material and Structures System Association, Daejeon (Korea, Republic of)

2017-04-15

Many composite materials are used in the aerospace industry because of their excellent mechanical properties. However, the nature of aviation exposes these materials to high temperature and high moisture conditions depending on climate, location, and altitude. Therefore, the molecular arrangement chemical properties, and mechanical properties of composite materials can be changed under these conditions. As a result, surface disruptions and cracks can be created. Consequently, moisture-impregnating defects can be induced due to the crack and delamination of composite materials as they are repeatedly exposed to moisture absorption moisture release, fatigue environment, temperature changes, and fluid pressure changes. This study evaluates the possibility of detecting the moisture-impregnating defects of CFRP and GFRP honeycomb structure sandwich composite materials, which are the composite materials in the aircraft structure, by using an active infrared thermography technology among non-destructive testing methods. In all experiments, it was possible to distinguish the area and a number of CFRP composite materials more clearly than those of GFRP composite material. The highest detection rate was observed in the heating duration of 50 mHz and the low detection rate was at the heating duration of over 500 mHz. The reflection method showed a higher detection rate than the transmission method.

The early warning system of landslides and sediment runoffs using meteorological condition including rainfall-soil moisture index (Invited)

Science.gov (United States)

Kubota, T.; Silva, I. C.; Hasnawir, H.

2009-12-01

The research including observation of rain, soil moisture content and sediment discharge is conducted on a torrent in northern Kyushu whose geology consists of Paleozoic metamorphic rocks (mainly schist) and whose vegetation consists of mainly Japanese cypress and cedar. Soil depth is approximately 50cm in average and permeability k is 0.1~0.01 order. With data obtained by the observation for more than 4 years, standard rainfalls of warning and evacuation against the sudden sediment runoffs are analyzed. Then, the result was compared with the ones in Nuevo Leon Mexico (geology of schist, slate, k=0.01~0.001 order) and in southern Sulawesi Island Indonesia (volcanic geology, k=0.001~0.0001 order). Hitherto, various methods were proposed to analyze the warning critical standard for landslide disaster or large sediment discharge. In this study, we employed Hirano's element slope runoff theory, the Self Organized Criticality Assumption (SOC), and the Elementary Catastrophe Theory (ETC) to analyze the data, although the soil moisture fluctuation, meteorological condition such as upper air wind and dew point depression, the rainfall-soil moisture index provided by Japan Meteorological Agency was considered. The last one is a cutting edge technology based on the tank model calculation of soil moisture content combined with short term rainfall prediction which is a product of numerical simulation using radar image advection analysis compensated with surface rain data and with orographic rain effect. In Hirano's theory, we can describe the critical rain Rc and rain intensity Ric as following equation. Q/A/M/ cosθ = Ri ∫(r*cosθ)dt = Ri*R (1) ∴ Ric*Rc = C (2) Here, Q: sediment runoff or debris flow discharge, A: watershed area, M: function concerning with sediment deposit features on the upstream torrents or slopes (porosity, torrent bed slope gradient, sediment accumulation length and depth, cohesion), t: time, θ: torrent bed or hillside slope gradient, r: instant

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.

The Combined Effect of Cold and Moisture on Manual Performance.

Science.gov (United States)

Ray, Matthew; Sanli, Elizabeth; Brown, Robert; Ennis, Kerri Ann; Carnahan, Heather

2018-02-01

Objective The aim of this study was to investigate the combined effect of cold and moisture on manual performance and tactile sensitivity. Background People working in the ocean environment often perform manual work in cold and wet conditions. Although the independent effects of cold and moisture on hand function are known, their combined effect has not been investigated. Method Participants completed sensory (Touch-Test, two-point discrimination) and motor (Purdue Pegboard, Grooved Pegboard, reef knot untying) tests in the following conditions: dry hand, wet hand, cold hand, and cold and wet hand. Results For the Purdue Pegboard and knot untying tasks, the greatest decrement in performance was observed in the cold-and-wet-hand condition, whereas the decrements seen in the cold-hand and wet-hand conditions were similar. In the Grooved Pegboard task, the performance decrements exhibited in the cold-and-wet-hand condition and the cold-hand condition were similar, whereas no decrement was observed in the wet-hand condition. Tactile sensitivity was reduced in the cold conditions for the Touch-Test but not the two-point discrimination test. The combined effect of cold and moisture led to the largest performance decrements except when intrinsic object properties helped with grasp maintenance. The independent effects of cold and moisture on manual performance were comparable. Application Tools and equipment for use in the cold ocean environment should be designed to minimize the effects of cold and moisture on manual performance by including object properties that enhance grasp maintenance and minimize the fine-dexterity requirements.

Design and Test of a Soil Profile Moisture Sensor Based on Sensitive Soil Layers

Science.gov (United States)

Liu, Cheng; Qian, Hongzhou; Cao, Weixing; Ni, Jun

2018-01-01

To meet the demand of intelligent irrigation for accurate moisture sensing in the soil vertical profile, a soil profile moisture sensor was designed based on the principle of high-frequency capacitance. The sensor consists of five groups of sensing probes, a data processor, and some accessory components. Low-resistivity copper rings were used as components of the sensing probes. Composable simulation of the sensor’s sensing probes was carried out using a high-frequency structure simulator. According to the effective radiation range of electric field intensity, width and spacing of copper ring were set to 30 mm and 40 mm, respectively. A parallel resonance circuit of voltage-controlled oscillator and high-frequency inductance-capacitance (LC) was designed for signal frequency division and conditioning. A data processor was used to process moisture-related frequency signals for soil profile moisture sensing. The sensor was able to detect real-time soil moisture at the depths of 20, 30, and 50 cm and conduct online inversion of moisture in the soil layer between 0–100 cm. According to the calibration results, the degree of fitting (R2) between the sensor’s measuring frequency and the volumetric moisture content of soil sample was 0.99 and the relative error of the sensor consistency test was 0–1.17%. Field tests in different loam soils showed that measured soil moisture from our sensor reproduced the observed soil moisture dynamic well, with an R2 of 0.96 and a root mean square error of 0.04. In a sensor accuracy test, the R2 between the measured value of the proposed sensor and that of the Diviner2000 portable soil moisture monitoring system was higher than 0.85, with a relative error smaller than 5%. The R2 between measured values and inversed soil moisture values for other soil layers were consistently higher than 0.8. According to calibration test and field test, this sensor, which features low cost, good operability, and high integration, is qualified for

Effect of Initial Moisture Content on the in-Vessel Composting Under Air Pressure of Organic Fraction of MunicipalSolid Waste in Morocco

Directory of Open Access Journals (Sweden)

Abdelhadi Makan

2013-01-01

Full Text Available This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts.For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times.This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications.

Effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco.

Science.gov (United States)

Makan, Abdelhadi; Assobhei, Omar; Mountadar, Mohammed

2013-01-03

This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts.For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times.This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications.

Effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco

Directory of Open Access Journals (Sweden)

Mountadar Mohammed

2013-01-01

Full Text Available Abstract This study aimed to evaluate the effect of initial moisture content on the in-vessel composting under air pressure of organic fraction of municipal solid waste in Morocco in terms of internal temperature, produced gases quantity, organic matter conversion rate, and the quality of the final composts. For this purpose, in-vessel bioreactor was designed and used to evaluate both appropriate initial air pressure and appropriate initial moisture content for the composting process. Moreover, 5 experiments were carried out within initial moisture content of 55%, 65%, 70%, 75% and 85%. The initial air pressure and the initial moisture content of the mixture showed a significant effect on the aerobic composting. The experimental results demonstrated that for composting organic waste, relatively high moisture contents are better at achieving higher temperatures and retaining them for longer times. This study suggested that an initial moisture content of around 75%, under 0.6 bar, can be considered as being suitable for efficient composting of organic fraction of municipal solid waste. These last conditions, allowed maximum value of temperature and final composting product with good physicochemical properties as well as higher organic matter degradation and higher gas production. Moreover, final compost obtained showed good maturity levels and can be used for agricultural applications.

Impact of groundwater capillary rises as lower boundary conditions for soil moisture in a land surface model

Science.gov (United States)

Vergnes, Jean-Pierre; Decharme, Bertrand; Habets, Florence

2014-05-01

Groundwater is a key component of the global hydrological cycle. It sustains base flow in humid climate while it receives seepage in arid region. Moreover, groundwater influences soil moisture through water capillary rise into the soil and potentially affects the energy and water budget between the land surface and the atmosphere. Despite its importance, most global climate models do not account for groundwater and their possible interaction with both the surface hydrology and the overlying atmosphere. This study assesses the impact of capillary rise from shallow groundwater on the simulated water budget over France. The groundwater scheme implemented in the Total Runoff Integrated Pathways (TRIP) river routing model in a previous study is coupled with the Interaction between Soil Biosphere Atmosphere (ISBA) land surface model. In this coupling, the simulated water table depth acts as the lower boundary condition for the soil moisture diffusivity equation. An original parameterization accounting for the subgrid elevation inside each grid cell is proposed in order to compute this fully-coupled soil lower boundary condition. Simulations are performed at high (1/12°) and low (0.5°) resolutions and evaluated over the 1989-2009 period. Compared to a free-drain experiment, upward capillary fluxes at the bottom of soil increase the mean annual evapotranspiration simulated over the aquifer domain by 3.12 % and 1.54 % at fine and low resolutions respectively. This process logically induces a decrease of the simulated recharge from ISBA to the aquifers and contributes to enhance the soil moisture memory. The simulated water table depths are then lowered, which induces a slight decrease of the simulated mean annual river discharges. However, the fully-coupled simulations compare well with river discharge and water table depth observations which confirms the relevance of the coupling formalism.

Impact of Soil Moisture Assimilation on Land Surface Model Spin-Up and Coupled LandAtmosphere Prediction

Science.gov (United States)

Santanello, Joseph A., Jr.; Kumar, Sujay V.; Peters-Lidard, Christa D.; Lawston, P.

2016-01-01

Advances in satellite monitoring of the terrestrial water cycle have led to a concerted effort to assimilate soil moisture observations from various platforms into offline land surface models (LSMs). One principal but still open question is that of the ability of land data assimilation (LDA) to improve LSM initial conditions for coupled short-term weather prediction. In this study, the impact of assimilating Advanced Microwave Scanning Radiometer for EOS (AMSR-E) soil moisture retrievals on coupled WRF Model forecasts is examined during the summers of dry (2006) and wet (2007) surface conditions in the southern Great Plains. LDA is carried out using NASAs Land Information System (LIS) and the Noah LSM through an ensemble Kalman filter (EnKF) approach. The impacts of LDA on the 1) soil moisture and soil temperature initial conditions for WRF, 2) land-atmosphere coupling characteristics, and 3) ambient weather of the coupled LIS-WRF simulations are then assessed. Results show that impacts of soil moisture LDA during the spin-up can significantly modify LSM states and fluxes, depending on regime and season. Results also indicate that the use of seasonal cumulative distribution functions (CDFs) is more advantageous compared to the traditional annual CDF bias correction strategies. LDA performs consistently regardless of atmospheric forcing applied, with greater improvements seen when using coarser, global forcing products. Downstream impacts on coupled simulations vary according to the strength of the LDA impact at the initialization, where significant modifications to the soil moisture flux- PBL-ambient weather process chain are observed. Overall, this study demonstrates potential for future, higher-resolution soil moisture assimilation applications in weather and climate research.

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 ...

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 ...

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

Evaluating the Utility of Remotely-Sensed Soil Moisture Retrievals for Operational Agricultural Drought Monitoring

Science.gov (United States)

Bolten, John D.; Crow, Wade T.; Zhan, Xiwu; Jackson, Thomas J.; Reynolds,Curt

2010-01-01

Soil moisture is a fundamental data source used by the United States Department of Agriculture (USDA) International Production Assessment Division (IPAD) to monitor crop growth stage and condition and subsequently, globally forecast agricultural yields. Currently, the USDA IPAD estimates surface and root-zone soil moisture using a two-layer modified Palmer soil moisture model forced by global precipitation and temperature measurements. However, this approach suffers from well-known errors arising from uncertainty in model forcing data and highly simplified model physics. Here we attempt to correct for these errors by designing and 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 modified Palmer soil moisture model. An assessment of soil moisture analysis products produced from this assimilation has been completed for a five-year (2002 to 2007) period over the North American continent between 23degN - 50degN and 128degW - 65degW. In particular, a data denial experimental approach is utilized to isolate the added utility of integrating remotely-sensed soil moisture by comparing EnKF soil moisture results obtained using (relatively) low-quality precipitation products obtained from real-time satellite imagery to baseline Palmer model runs forced with higher quality rainfall. An analysis of root-zone anomalies for each model simulation suggests that the assimilation of AMSR-E surface soil moisture retrievals can add significant value to USDA root-zone predictions derived from real-time satellite precipitation products.

On the spatial distribution of the transpiration and soil moisture of a Mediterranean heterogeneous ecosystem in water-limited conditions.

Science.gov (United States)

Curreli, Matteo; Corona, Roberto; Montaldo, Nicola; Albertson, John D.; Oren, Ram

2014-05-01

trees to obtain a generalized estimates of sapwood depth. The known of allometric relationships between sapwood area, diameter and canopy cover area within the eddy covariance footprint helped for the application of a reliable scaling procedure of the local sap flow estimates which are in a good agreement with the estimates of ET eddy covariance based. Soil moisture were also extensively monitored through 25 probes installed in the eddy covariance footprint. Results show that comparing eddy covariance and sap flow ET estimates eddy covariance technique is still accurate in this heterogeneous field, whereas the key assumption, surface homogeneity, is not preserved. Furthermore, interestingly wild olives still transpire at higher rates for the driest soil moisture conditions, confirming the hydraulic redistribution from soil below the roots, and from roots penetrating deep cracks in the underlying basalt parent rock.

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.

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.

Comparing the ensemble and extended Kalman filters for in situ soil moisture assimilation with contrasting conditions

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D. Fairbairn

2015-12-01

Full Text Available Two data assimilation (DA methods are compared for their ability to produce an accurate soil moisture analysis using the Météo-France land surface model: (i SEKF, a simplified extended Kalman filter, which uses a climatological background-error covariance, and (ii EnSRF, the ensemble square root filter, which uses an ensemble background-error covariance and approximates random rainfall errors stochastically. In situ soil moisture observations at 5 cm depth are assimilated into the surface layer and 30 cm deep observations are used to evaluate the root-zone analysis on 12 sites in south-western France (SMOSMANIA network. These sites differ in terms of climate and soil texture. The two methods perform similarly and improve on the open loop. Both methods suffer from incorrect linear assumptions which are particularly degrading to the analysis during water-stressed conditions: the EnSRF by a dry bias and the SEKF by an over-sensitivity of the model Jacobian between the surface and the root-zone layers. These problems are less severe for the sites with wetter climates. A simple bias correction technique is tested on the EnSRF. Although this reduces the bias, it modifies the soil moisture fluxes and suppresses the ensemble spread, which degrades the analysis performance. However, the EnSRF flow-dependent background-error covariance evidently captures seasonal variability in the soil moisture errors and should exploit planned improvements in the model physics. Synthetic twin experiments demonstrate that when there is only a random component in the precipitation forcing errors, the correct stochastic representation of these errors enables the EnSRF to perform better than the SEKF. It might therefore be possible for the EnSRF to perform better than the SEKF with real data, if the rainfall uncertainty was accurately captured. However, the simple rainfall error model is not advantageous in our real experiments. More realistic rainfall error models are

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.

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.

Influence of sulfur dioxide and ozone on vegetation of bean and barley plants under different soil moisture conditions

Energy Technology Data Exchange (ETDEWEB)

Markowski, A; Grzesiak, S

1974-01-01

The effects of toxic gases on extent of injuries to assimilating surface, dry weight yields, and generative development in bean and barley were studied in three successive phases of vegetation under conditions of optimum soil moisture and of drought just above the wilting point. Experiments with ozone and sulfur dioxide on bean and SO/sub 2/ on barley demonstrate that the susceptibility of plants to toxic gases decrease under drought conditions that cause a temporary dehydration of tissues. Determinations of sulfate sulfur contents in different plant organs show that a lower hydration of tissues is accompanied by lower adsorption of sulfur dioxide.

Moisture effect on the dielectric response and space charge behaviour of mineral oil impregnated paper insulation

International Nuclear Information System (INIS)

Hao Jian; Liao Ruijin; Chen, George

2011-01-01

Dielectric response and space charge behaviour of oil-paper insulation sample with different moisture contents were investigated using the frequency dielectric spectroscopy (FDS) and the pulsed electroacoustic (PEA) technique, respectively. The influence of moisture on the dielectric response and space charge behaviour of oil impregnated paper insulation was analysed. Results show that the moisture has great effect on the FDS and space charge behaviour of oil impregnated paper insulation. In the frequency range of 10 -2 ∼10 6 Hz, the conductivity and the capacitance of oil impregnated paper increases with its moisture content. The space charge distribution of oil-paper sample with lower and higher moisture contents is very different from each other. The higher the moisture concentration of the oil impregnated paper, the easier the negative charge penetration into the insulation paper. There is a significant amount of positive charge accumulated at the paper-paper interface near to the cathode for oilpaper sample with lower moisture content. However, the positive charge appears in the middle layer paper for oil-paper sample with higher moisture content. Due to the high conductivity, the charge trapped in the oil-paper sample with higher moisture content disappears much faster than that in the oil-paper sample with lower moisture content after removing the voltage.

Moisture effect on the dielectric response and space charge behaviour of mineral oil impregnated paper insulation

Energy Technology Data Exchange (ETDEWEB)

Hao Jian; Liao Ruijin [State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University (China); Chen, George, E-mail: jh210v@ecs.soton.ac.uk [School of Electronics and Computer Science, University of Southampton (United Kingdom)

2011-08-12

Dielectric response and space charge behaviour of oil-paper insulation sample with different moisture contents were investigated using the frequency dielectric spectroscopy (FDS) and the pulsed electroacoustic (PEA) technique, respectively. The influence of moisture on the dielectric response and space charge behaviour of oil impregnated paper insulation was analysed. Results show that the moisture has great effect on the FDS and space charge behaviour of oil impregnated paper insulation. In the frequency range of 10{sup -2}{approx}10{sup 6}Hz, the conductivity and the capacitance of oil impregnated paper increases with its moisture content. The space charge distribution of oil-paper sample with lower and higher moisture contents is very different from each other. The higher the moisture concentration of the oil impregnated paper, the easier the negative charge penetration into the insulation paper. There is a significant amount of positive charge accumulated at the paper-paper interface near to the cathode for oilpaper sample with lower moisture content. However, the positive charge appears in the middle layer paper for oil-paper sample with higher moisture content. Due to the high conductivity, the charge trapped in the oil-paper sample with higher moisture content disappears much faster than that in the oil-paper sample with lower moisture content after removing the voltage.

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 %.

The effect of moisture content on physicochemical properties of extruded waxy and non-waxy rice flour.

Science.gov (United States)

Jongsutjarittam, Ornpicha; Charoenrein, Sanguansri

2014-12-19

The properties of waxy rice flour (WRF) and non-waxy rice flour (RF) were modified using an extrusion process with different feeding material moisture contents. WRF was more affected by the thermomechanical stress from extrusion; consequently, it had a lower glass transition temperature but higher water solubility index (WSI) indicating higher molecular degradation than extruded RF. The lower moisture content of the feeding flour caused more severe flour damage (coarser surface of the extruded flour) and lowered relative crystallinity compared to higher moisture content processing. Moreover, low moisture content processing led to complete gelatinization, whereas, partial gelatinization occurred in the higher moisture content extrusion. Consequently, the extruded flours had a lower peak viscosity and gelatinization enthalpy but a higher water absorption index and WSI than native flour. In conclusion, the rice flour type and the moisture content of the extrusion feeding flour affected the physicochemical properties of the extruded flour. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of moisture content on some physical and mechanical properties of juvenile rubberwood (Hevea brasiliensis Muell. Arg.

Directory of Open Access Journals (Sweden)

Buhnnum Kyokong

2003-05-01

Full Text Available Moisture content of rubberwood is an important factor influencing its physical and mechanical behaviours. This research aimed at quantifying effect of moisture content on physical and mechanical properties of juvenile rubberwood core. The specimens at various moisture contents were tested in compression and shear parallel to grain. Information was gathered to determine shrinkage, density and specific gravity of specimens. The equilibrium moisture content determined from desorption experiment, was well described by the Hailwood-Horrobin solution theory. Moisture content of 23+4% best represented the value of apparent fiber saturation point, Mp, determined from physical and mechanical properties data. Above Mp, values of all physical and mechanical properties examined were fairly constant. Maximum volumetric shrinkage from moisture content above Mp to an oven-dry condition was 8.2+1.8%. Specific gravity and density were 0.55+0.03 and 614+30 kg/m3 at 12% moisture content. Below Mp, ultimate compressive stress (UCS parallel to grain, ultimate shear stress parallel to grain, modulus of elasticity (MOE for compression parallel to grain, and shear modulus parallel to grain increased exponentially with decreasing moisture content. Shear strain at fracture and work to fracture of shear parallel to grain were found to increase as moisture content decreased below Mp and attained the maximum values at 20% and 12% moisture content, respectively. The values decreased with further lowering of the level of moisture content. Ultimate compressive stress (UCS parallel to grain was closely correlated with specific gravity and was more sensitive to changes in moisture content at higher specific gravity level.

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

RESTORATION OF LONG-FALLOW LANDS IN THE CONDITIONS OF THE INCREASED MOISTURE

Directory of Open Access Journals (Sweden)

N. I. Dzhabborov

2015-01-01

Full Text Available The agricultural lands, which are not used in a crop rotation, grow over with weed vegetation forming a thick sod cover. The greatest damage is caused by overgrowing of the farmland a bush and a half-grown forest. Especially it is shown in the conditions of the increased moisture. Technologies and technical means for restoration of not cultivated lands should correspond to conditions of zone specifics. The volume and rates of introduction of the long-fallow lands depend on technical equipment of the agricultural enterprises. The combined soil-cultivating unit Leader-2.5Н and the modular ring harrows Lider-BKM-6 were tested. They intended for introduction of fallow lands. These machines are worked out by JSC Sibirskiy Agropromyshlennyy Dom (Novosibirsk. Hardness of the soil changes depending on processing depth. In the 0-10 cm layer it decreases from 13 to 8.2-8.3 kg/sq•cm, in a layer of 10-20 cm - from 18.7 to 9.7-12.8 kg/cc, at a depth of 20-30 cm - from 26.1 to 15.7-24.1 kg/sq•cm. It was showed that energy consumption on recovery of 1 hа of wetlands make 1932.24 MJ that is equivalent 45.25 kg of diesel fuel.

Tools for Performance Simulation of Heat, Air and Moisture Conditions of Whole Buildings

DEFF Research Database (Denmark)

Woloszyn, Monika; Rode, Carsten

2008-01-01

Humidity of indoor air is an important factor influencing the air quality and energy consumption of buildings as well as durability of building components. Indoor humidity depends on several factors, such as moisture sources, air change, sorption in materials and possible condensation. Since all...... and moisture transfer processes that take place in “whole buildings” by considering all relevant parts of its constituents. It is believed that full understanding of these processes for the whole building is absolutely crucial for future energy optimization of buildings, as this cannot take place without...

INFLUENCE OF TEMPERATURE AND RELATIVE HUMIDITY ON GRAIN MOISTURE, GERMINATION AND VIGOUR OF THREE WHEAT CULTIVARS DURING ONE YEAR STORAGE

Directory of Open Access Journals (Sweden)

Ivica Strelec

2010-12-01

Full Text Available Changes in grain moisture, germination and vigour of three wheat cultivars packed in paper bags and stored for one year under four different conditions of environmental temperature and relative humidity (RH were investigated. During the first ninety days of storage significant reduction in grain moisture content of 4, 2.5 and 0.9 %, respectively, under 40 °C, 25 °C and 4 °C and RH of 45 % occurred. Subsequently grain moisture remained constant until the end of storage. Seeds of examined cultivars lost their germination ability and vigour only under elevated storage temperatures. Germination and vigour loss after one year of storage differed between cultivars being higher for seeds kept under 40°C, RH = 45% (35-85 % and 55-94 %, respectively, than under 25°C, RH = 45 % (10-20 % and 15-22 %, respectively. Obtained data indicate significant influence of storage conditions on moisture content, germination and vigour changes during storage of wheat seeds, as well as varietal dependence of seed viability.

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).

Using Whole-House Field Tests to Empirically Derive Moisture Buffering Model Inputs

Energy Technology Data Exchange (ETDEWEB)

Woods, J.; Winkler, J.; Christensen, D.; Hancock, E.

2014-08-01

Building energy simulations can be used to predict a building's interior conditions, along with the energy use associated with keeping these conditions comfortable. These models simulate the loads on the building (e.g., internal gains, envelope heat transfer), determine the operation of the space conditioning equipment, and then calculate the building's temperature and humidity throughout the year. The indoor temperature and humidity are affected not only by the loads and the space conditioning equipment, but also by the capacitance of the building materials, which buffer changes in temperature and humidity. This research developed an empirical method to extract whole-house model inputs for use with a more accurate moisture capacitance model (the effective moisture penetration depth model). The experimental approach was to subject the materials in the house to a square-wave relative humidity profile, measure all of the moisture transfer terms (e.g., infiltration, air conditioner condensate) and calculate the only unmeasured term: the moisture absorption into the materials. After validating the method with laboratory measurements, we performed the tests in a field house. A least-squares fit of an analytical solution to the measured moisture absorption curves was used to determine the three independent model parameters representing the moisture buffering potential of this house and its furnishings. Follow on tests with realistic latent and sensible loads showed good agreement with the derived parameters, especially compared to the commonly-used effective capacitance approach. These results show that the EMPD model, once the inputs are known, is an accurate moisture buffering model.

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.

Exchange of moisture between atmosphere and ground regarding tritium transfer

International Nuclear Information System (INIS)

Bunnenberg, C.

1980-09-01

Two measuring equipment have been developed in the framework of this study which fulfill important conditions to avoid microclimatic interferences during measurement by using site-specific ground samples and embedding these in the ground surface. The beta-absorption lysimeter allows the detection of a minimum deposit height of 0.001 mm in a 1 mm sample layer. The conductivity moisture probe is to measure the moisture diffusion within the first 80 mm of the upper ground with a vertical spacial resolution of 2 mm. It is possible to measure a minimum water content increase of 0.02 wt% per 2 mm ground layer using this probe. The influences of single microclimatic parameter on condensation and evaporation were investigated and a transport equation was developed. Investigations in the Negev proved the application ability of the measuring equipment. The application of the transport equation showed very good agreement with the measured values. When the ground surface starts to cool in the afternoon, there is a countercurrent moisture transport from the atmosphere and the deeper ground layers which lead to a higher water content in the upper ground layer. At about 50 mm depth there is an overlapping layer of the two moisture flows which remains almost constant over the 24 h cycle. This exchange zone of atmospheric humidity and ground water must be paid great attention with regard to HTO transfer. (orig./HP) [de

Impacts of an Innovative Residential Construction Method on Internal Conditions

Directory of Open Access Journals (Sweden)

Roger Birchmore

2015-02-01

Full Text Available New Zealand houses are known for producing sub-optimal internal thermal conditions and unacceptably high internal moisture levels. These contribute to poor levels of health, mould and can coincide with the decay of structural timber frames. A proposed solution is to provide an alternative structure utilising plywood, a vapour check on the internal face of the timber frame and an additional air gap, followed by the internal lining. The internal vapour check is designed to prevent moisture vapour diffusion from inside into the frame and to permit moisture diffusion from outside through the structure to the internal environment. Two full scale houses had temperatures, dew points and humidity levels monitored in passive, unoccupied conditions. The test case house incorporated the innovative construction solution. The control house was of identical design and location, using standard construction practice. The calculated internal moisture content profile appeared to be unrelated to the external moisture content as expected, instead following the profile of the changing internal temperature. Whilst the innovative construction appeared to prevent moisture diffusion into the structure in winter and permit it inside in summer, this resulted in a generally higher internal relative humidity than the control house.

Influence of Soil Moisture on Litter Respiration in the Semiarid Loess Plateau

Science.gov (United States)

Zhang, Yanjun; Guo, Shengli; Liu, Qingfang; Jiang, Jishao

2014-01-01

Understanding the response mechanisms of litter respiration to soil moisture in water-limited semi-arid regions is of vital importance to better understanding the interplay between ecological processes and the local carbon cycle. In situ soil respiration was monitored during 2010–2012 under various conditions (normal litter, no litter, and double litter treatments) in a 30-year-old artificial black locust plantation (Robinia pseudoacacia L.) on the Loess Plateau. Litter respiration with normal and double litter treatments exhibited similar seasonal variation, with the maximum value obtained in summer (0.57 and 1.51 μmol m−2 s−1 under normal and double litter conditions, respectively) and the minimum in spring (0.27 and 0.69 μmol m−2 s−1 under normal and double litter conditions, respectively). On average, annual cumulative litter respiration was 115 and 300 g C m−2 y−1 under normal and double litter conditions, respectively. Using a soil temperature of 17°C as the critical point, the relationship between litter respiration and soil moisture was found to follow quadratic functions well, whereas the determination coefficient was much greater at high soil temperature than at low soil temperature (33–35% vs. 22–24%). Litter respiration was significantly higher in 2010 and 2012 than in 2011 under both normal litter (132–165 g C m−2 y−1 vs. 48 g C m−2 y−1) and double litter (389–418 g C m−2 y−1 vs. 93 g C m−2 y−1) conditions. Such significant interannual variations were largely ascribed to the differences in summer rainfall. Our study demonstrates that, apart from soil temperature, moisture also has significant influence on litter respiration in semi-arid regions. PMID:25474633

Influence of soil moisture on uptake and utilization of applied nitrogen in tea

International Nuclear Information System (INIS)

Marimuthu, S.; Raj Kumar, R.

1999-01-01

An experiment was conducted with pot-grown young tea plants to study N uptake under different soil moisture regime. Labelled urea nitrogen was found effectively utilized under rainfed conditions. However, N loss through percolation/leaching in response to saturated moisture was as high as 33.3%. Plants grown under controlled conditions utilized less amount of applied N and the rest was retained in the soil. Unaccounted loss, in both the cases, was approximately 9%. Fertilizer-use efficiency of young tea plants under rain fed conditions was about 35% while it was 15% under moisture deficient conditions. Results on N balance in tea soils are discussed. (author)

Toxicity interaction between chlorpyrifos, mancozeb and soil moisture to the terrestrial isopod Porcellionides pruinosus.

Science.gov (United States)

Morgado, Rui G; Gomes, Pedro A D; Ferreira, Nuno G C; Cardoso, Diogo N; Santos, Miguel J G; Soares, Amadeu M V M; Loureiro, Susana

2016-02-01

A main source of uncertainty currently associated with environmental risk assessment of chemicals is the poor understanding of the influence of environmental factors on the toxicity of xenobiotics. Aiming to reduce this uncertainty, here we evaluate the joint-effects of two pesticides (chlorpyrifos and mancozeb) on the terrestrial isopod Porcellionides pruinosus under different soil moisture regimes. A full factorial design, including three treatments of each pesticide and an untreated control, were performed under different soil moisture regimes: 25%, 50%, and 75% WHC. Our results showed that soil moisture had no effects on isopods survival, at the levels assessed in this experiment, neither regarding single pesticides nor mixture treatments. Additivity was always the most parsimonious result when both pesticides were present. Oppositely, both feeding activity and biomass change showed a higher sensitivity to soil moisture, with isopods generally showing worse performance when exposed to pesticides and dry or moist conditions. Most of the significant differences between soil moisture regimes were found in single pesticide treatments, yet different responses to mixtures could still be distinguished depending on the soil moisture assessed. This study shows that while soil moisture has the potential to influence the effects of the pesticide mixture itself, such effects might become less important in a context of complex combinations of stressors, as the major contribution comes from its individual interaction with each pesticide. Finally, the implications of our results are discussed in light of the current state of environmental risk assessment procedures and some future perspectives are advanced. Copyright © 2015 Elsevier Ltd. All rights reserved.

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 ...

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

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.

Experimental on moisture migration and pore pressure formation of concrete members subjected to high temperature

International Nuclear Information System (INIS)

Nagao, Kakuhiro; Nakane, Sunao

1993-01-01

The experimental studies concerning temperature, moisture migration, and pore pressure of mass concrete mock-up specimens heated up to high temperature at 110degC to 600degC, were performed, so as to correctly estimate the moisture migration behaviour of concrete members subjected to high temperature, which is considered significantly influenced on physical properties of concrete. As a results, it is confirmed that the moisture migration behavior of concrete members can be explained by temperature and pore pressure, and indicate the characteristics both sealed condition (dissipation of moisture is prevented) and unsealed condition (dissipation of moisture occur). (author)

Surface moisture estimation in urban areas

Science.gov (United States)

Jiang, Yitong

) model was used to estimate soil moisture and ET and fractional cover of urban landscape was used to estimate soil moisture and ET over vegetation, soil, and impervious surfaces. The results of this dissertation showed the general trend of daily and hourly soil moisture and ET over vegetation, soil, and impervious surfaces in summer, fall, and winter seasons, and the response of soil moisture and ET to precipitations over three types of land covers. In summer, hourly soil moisture fluctuates yet stable; during frequent precipitation, hourly ET over soil and impervious surface show similar patterns, while vegetation surfaces yielded lower ET, which indicated that the distribution and change of surface moisture is associated with the distribution and vigor of urban trees. From fall to winter, the general trend of soil moisture and ET were found decreased, and response to precipitations becomes weaker in winter. The spatial distribution of ET shows that the central urban area has higher ET than regular impervious surfaces and the city's average, which indicate the distribution of surface moisture is associated with the structural complexity of buildings. The two hypotheses were supported, and the methodology is tested to be effective in surface moisture estimation in urban areas. The results suggested future studies on the impact of anthropogenic heat on surface moisture and the data integrity issue in multiple data source in urban areas.

TAKING VARIOUS AGRO-TECHNICAL MEASURES FOR THE PRESERVATION AND ACCUMULATION OF MOISTURE

Directory of Open Access Journals (Sweden)

M. B. Khalilov

2016-01-01

Full Text Available ARTICLE RETRACTEDAim. The aim is to conduct a theoretical study of the conditions of occurrence of surface runoff and take technical measures for its prevention.Discussion. The occurrence of surface runoff is possible on condition that the intensity of moisture entry per time unit is greater than the intensity of its absorption and passage through the topsoil. Conditions of surface runoff occur at high intensity of moisture entering the soil surface which can be in the case of heavy rainfall, low water permeability of topsoil as a result of the increased density. The upper topsoil not affected by loosening passes moisture worse than loosened. Low water conductivity of the arable layer may be due to the fact that it is saturated with moisture up to the limit, and the underlying subsoil layers do not absorb or absorb not enough water, pass water less than enters through the upper topsoil. This phenomenon leads to oversaturation of the top plowed layer by water, which can lead to water erosion and landslide.Conclusion. We obtained analytical expressions describing the process of accumulation of moisture in the soil and the formation of surface runoff, which also allow to theoretically justify the need for different agronomic techniques impact on soil. We should select tools and soil impact techniques in order to preserve and accumulate moisture with account of the certain agrolandscape conditions specific to these fields.

Relaxation behavior of radicals produced in irradiated black pepper under various moisture conditions by ESR

International Nuclear Information System (INIS)

Kameya, Hiromi; Kawauchi, Risa; Shimoyama, Yuhei; Kaeda, Yoko; Ogawa, Satoko; Nakamura, Hideo; Ukai, Mitsuko

2008-01-01

Black pepper is easy to be contaminated by microorganism and often processed to γ-irradiation. ESR has been used for the detection of radicals induced in irradiated spices. Using ESR, we revealed the effects of moisture condition during storage of irradiated black pepper on the saturation behavior of ESR signal. The ESR spectrum of black pepper consists of a broad sextet centered at g=2.0, a singlet as same g-value and a singlet at g=4.0. The irradiation causes two new signals, one is the strong and sharp singlet signal at g=2.0 and the other is the side signal. We found that the signal intensity originated by the radicals of black pepper with and without radiation decayed in the high humidity condition during storage. The ESR signal intensity of irradiated black pepper decayed during storage and showed almost the same intensity level as that of non-irradiated black pepper during storage. (author)

Northern Hemisphere moisture variability during the Last Glacial period

Science.gov (United States)

Asmerom, Y.; Polyak, V. J.; Lachniet, M. S.

2013-12-01

It was previously shown that large oxygen isotope variability related to changing moisture sources in the southwestern United States (SW) match the Greenland ice core temperature record. The variations were attributed to changes in the ratio of winter to summer precipitation delivered to the SW, with lighter winter δ18O values compared to summer monsoon rainfall, due to meridonial shifts in the position of the polar jet stream, which directs winter storm tracks. Cold stadial δ18O excursions are associated with strongly negative values, while interstadials have higher than average δ18O values. Although these data documented moisture source variability to the SW, the question of effective moisture variability remains unanswered. Here we present new high-resolution δ18O and δ13C isotopic data from a precisely dated speleothem, FS-AH1, from Fort Stanton Cave, New Mexico USA. The sample grew continuously between 47.6 and 11.1 kyr. The new chronology is more precise than previous work due to high sample growth rate, new gains in efficiency provided by our upgraded Neptune MC-ICPMS and new more precise determinations of the half-lives of 230Th and 234U. The FS-AH1 δ18O and the Greenland δ18O data (on the GICC05 time scale) show a remarkable match, both with respect to stadials/interstadial amplitudes and variability, and in the overall long-term trend. Our interpretation of the δ18O data remains the same, an indicator of moisture source variability. The δ18O and δ13C isotopic data show no correlation (R2 effective moisture in the soil zone overlying the cave, with low δ13C attributed to high soil productivity, high effective moisture, and wet conditions. The stadial and interstadial events are expressed mutely, if at all, in the δ13C data, while the secular variation follows the change in Northern Hemisphere summer insolation (insolation), similar to other Northern Hemisphere data, such as the strength of the East Asian summer monsoon as recorded in the Hulu

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.

A relook at NEH-4 curve number data and antecedent moisture condition criteria

Science.gov (United States)

Mishra, Surendra Kumar; Singh, Vijay P.

2006-08-01

This paper investigates the variation of the popular curve number (CN) values given in the National Engineering Hand Book-Section 4 (NEH-4) of the Soil Conservation Service (SCS) with antecedent moisture condition (AMC) and soil type. Using the volumetric concept, involving soil, water, and air, a significant condensation of the NEH-4 tables is achieved. This leads to a procedure for determination of CN for gauged as well as ungauged watersheds. The rainfall-runoff events derived from daily data of four Indian watersheds exhibited a power relation between the potential maximum retention or CN and the 5-day antecedent rainfall amount. Including this power relation, the SCS-CN method was modified. This modification also eliminates the problem of sudden jumps from one AMC level to the other. The runoff values predicted using the modified method and the existing method utilizing the NEH-4 AMC criteria yielded similar results.

New calculation method to solve moisture balance in the room with regenerator heat recovery and infiltration

DEFF Research Database (Denmark)

Pomianowski, Michal Zbigniew; Heiselberg, Per; Drivsholm, Christian

2017-01-01

This paper investigates moisture related performance of a regenerator heat exchanger located in a decentralized ventilation unit for residential building application. The decentralized ventilation solutions have recently become a more and more popular alternative to centralized ventilation systems...... in air handling units (AHUs). In the case of regenerator heat exchanger, the higher the heat recovery efficiency obtained the higher risk that condensation might occur. This condensation might form small droplets on the surface of the regenerator that might not be possible to drain in the short switching...... time of the regenerator and consequently might be evaporated in the next cycle back to the building and cause elevated humidity conditions in the indoor spaces. Due to the fact that the traditionally used dilution equation must not be used to solve moisture balance in the room with regenerator heat...

Translocation of 14C-photosynthates under normal and moisture stress conditions in finger millet (Eleusine coracana) gaertin

International Nuclear Information System (INIS)

Udayakumar, M.; Rama Rao, S.; Krishna Sastry, K.S.

1981-01-01

Translocation of photosynthates into different sinks was studied following feeding a single leaf with 14 CO 2 in 40 day old stressed and non-stressed plants of Eleusine coracana. The rate of efflux of 14 C-photosynthates was twice as much in non-stressed plants compared to stressed plants. Young developing leaves, stem apex and stem which are the potential sinks under non-stressed conditions received very little activity under stress conditions. Percent activity in the roots was enhanced under stress suggesting the pattern of translocation was altered under stress conditions. In the plants subjected to moisture stress, after feeding with 14 CO 2 the rate of efflux of 14 C-photosynthates from the fed leaf decreased and the pattern of translocation was altered. Though the effect of stress seems to be directly on the translocation system, the photosynthetic rate appears to be more sensitive to stress than translocation. (author)

Evaluation of Enterococcus faecium NRRL B-2354 as a Surrogate for Salmonella During Extrusion of Low-Moisture Food.

Science.gov (United States)

Verma, Tushar; Wei, Xinyao; Lau, Soon Kiat; Bianchini, Andreia; Eskridge, Kent M; Subbiah, Jeyamkondan

2018-04-01

Salmonella in low-moisture foods is an emerging challenge due to numerous food product recalls and foodborne illness outbreaks. Identification of suitable surrogate is critical for process validation at industry level due to implementation of new Food Safety Modernization Act of 2011. The objective of this study was to evaluate Enterococcus faecium NRRL B-2354 as a surrogate for Salmonella during the extrusion of low-moisture food. Oat flour, a low-moisture food, was adjusted to different moisture (14% to 26% wet basis) and fat (5% to 15% w/w) contents and was inoculated with E. faecium NRRL B-2354. Inoculated material was then extruded in a lab-scale single-screw extruder running at different screw speeds (75 to 225 rpm) and different temperatures (75, 85, and 95 °C). A split-plot central composite 2nd order response surface design was used, with the central point replicated six times. The data from the selective media (m-Enterococcus agar) was used to build the response surface model for inactivation of E. faecium NRRL B-2354. Results indicated that E. faecium NRRL B-2354 always had higher heat resistance compared to Salmonella at all conditions evaluated in this study. However, the patterns of contour plots showing the effect of various product and process parameters on inactivation of E. faecium NRRL B-2354 was different from that of Salmonella. Although E. faecium NRRL B-2354 may be an acceptable surrogate for extrusion of low-moisture products due to higher resistance than Salmonella, another surrogate with similar inactivation behavior may be preferred and needs to be identified. Food Safety Modernization Act requires the food industry to validate processing interventions. This study validated extrusion processing and demonstrated that E. faecium NRRL B-2354 is an acceptable surrogate for extrusion of low-moisture products. The developed response surface model allows the industry to identify process conditions to achieve a desired lethality for their

High Pressure Compression-Molding of α-Cellulose and Effects of Operating Conditions

Directory of Open Access Journals (Sweden)

Antoine Rouilly

2013-05-01

Full Text Available Commercial α-cellulose was compression-molded to produce 1A dog-bone specimens under various operating conditions without any additive. The resulting agromaterials exhibited a smooth, plastic-like surface, and constituted a suitable target as replacement for plastic materials. Tensile and three-points bending tests were conducted according to ISO standards related to the evaluation of plastic materials. The specimens had strengths comparable to classical petroleum-based thermoplastics. They also exhibited high moduli, which is characteristic of brittle materials. A higher temperature and higher pressure rate produced specimens with higher mechanical properties while low moisture content produced weaker specimens. Generally, the strong specimen had higher specific gravity and lower moisture content. However, some parameters did not follow the general trend e.g., thinner specimen showed much higher Young’s Modulus, although their specific gravity and moisture content remained similar to control, revealing a marked skin-effect which was confirmed by SEM observations.

Massless representations and admissibility condition for higher spin superalgebras

Energy Technology Data Exchange (ETDEWEB)

Konstein, S E; Vasiliev, M A

1989-01-16

Massless particle representations of various infinite-dimensional higher spin superalgebras proposed previously are constructed. We analyse which of higher spin superalgebras obey the requirement (the admissibility condition) of possessing massless unitary representations with the same spectra of spins as predicted by the structure of gauge fields originating from these superalgebras. It is argued that those higher spin superalgebras, which obey the admissibility condition, can serve as rigid supersymmetries in nontrivial consistent gauge theories of massless fields of all spins.

Modeling of the process of moisture loss during the storage of dried apricots.

Science.gov (United States)

Miranda, G; Berna, A; Bon, J; Mulet, A

2011-10-01

Moisture content is a reference parameter for dried food because the growth of most microorganisms is inhibited below certain water activity levels. In addition, it has a determining influence on the evolution of important parameters, such as color and flavor, and on other properties and deterioration reactions, such as texture, oxidation processes and nutritional value. During the storage of some dried fruits, moisture is produced due to Maillard reactions and exchanged with the surrounding environment through the packaging. The evolution of dried foods during their shelf life depends on the storage conditions. The aim of this study is to analyze the evolution of the moisture content in dried apricots packaged in different types of containers, namely glass and thermosealed polypropylene trays. The samples were stored at constant temperatures: 5, 15, 25 and 35 °C and were analyzed periodically over a period of 12 months. The sorption isotherms of apricots used in this study were also determined. In order to model how the moisture evolved, an empirical kinetic model was tested. This model considers both water transfer from the fruit and also water production as a result of the Maillard processes. The explained variance was higher than 95% in the samples stored in trays, which were thermosealed with film.

Multidimensional HAM-conditions

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place

Heat, Air and Moisture (HAM) conditions, experimental data are needed. Tests were performed in the large climate simulator at SBi involving full-scale wall elements. The elements were exposed for steady-state conditions, and temperature cycles simulating April and September climate in Denmark....... The effect on the moisture and temperature conditions of the addition of a vapour barrier and an outer cladding on timber frame walls was studied. The report contains comprehensive appendices documenting the full-scale tests. The tests were performed as a part of the project 'Model for Multidimensional Heat......, Air and Moisture Conditions in Building Envelope Components' carried out as a co-project between DTU Byg and SBi....

Influence of moisture stress on growth, dry matter yield and ...

African Journals Online (AJOL)

The effects of moisture stress were evaluated in four Indigofera species (I. amorphoides, I. arrecta, I. coerulea and I. vicioides) using a pot experiment under glasshouse conditions. The aim was to examine the influence of moisture-deficit stress on physiological attributes and performance of the four Indigofera species.

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.

The role of the antecedent soil moisture condition on the distributed hydrologic modelling of the Toce alpine basin floods.

Science.gov (United States)

Ravazzani, G.; Montaldo, N.; Mancini, M.; Rosso, R.

2003-04-01

Event-based hydrologic models need the antecedent soil moisture condition, as critical boundary initial condition for flood simulation. Land-surface models (LSMs) have been developed to simulate mass and energy transfers, and to update the soil moisture condition through time from the solution of water and energy balance equations. They are recently used in distributed hydrologic modeling for flood prediction systems. Recent developments have made LSMs more complex by inclusion of more processes and controlling variables, increasing parameter number and uncertainty of their estimates. This also led to increasing of computational burden and parameterization of the distributed hydrologic models. In this study we investigate: 1) the role of soil moisture initial conditions in the modeling of Alpine basin floods; 2) the adequate complexity level of LSMs for the distributed hydrologic modeling of Alpine basin floods. The Toce basin is the case study; it is located in the North Piedmont (Italian Alps), and it has a total drainage area of 1534 km2 at Candoglia section. Three distributed hydrologic models of different level of complexity are developed and compared: two (TDLSM and SDLSM) are continuous models, one (FEST02) is an event model based on the simplified SCS-CN method for rainfall abstractions. In the TDLSM model a two-layer LSM computes both saturation and infiltration excess runoff, and simulates the evolution of the water table spatial distribution using the topographic index; in the SDLSM model a simplified one-layer distributed LSM only computes hortonian runoff, and doesn’t simulate the water table dynamic. All the three hydrologic models simulate the surface runoff propagation through the Muskingum-Cunge method. TDLSM and SDLSM models have been applied for the two-year (1996 and 1997) simulation period, during which two major floods occurred in the November 1996 and in the June 1997. The models have been calibrated and tested comparing simulated and

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.

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.

[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.

The effects of moisture and temperature variations on the long term durability of polymer concrete

DEFF Research Database (Denmark)

Barbosa, Ricardo; Hansen, Kurt Kielsgaard; Grelk, Bent

2013-01-01

The use of polymer concrete to precast products in construction presents normally many advantages compared to traditional concrete. Higher strength, lower permeability, shorter curing periods, better chemical resistances and a better durability is normally predicated, however this is a research...... and after exposure to different thermal conditions is very important. In this paper, an experimental study concerning the influence of temperature and moisture in cyclic conditions on the durability of polymer concrete based on an unsaturated polyester resin is described and the results are presented...

U.S National cropland soil moisture monitoring using SMAP

Science.gov (United States)

Crop condition information is critical for public and private sector decision making that concerns agricultural policy, food production, food security, and food commodity prices. Crop conditions change quickly due to various growing condition events, such as temperature extremes, soil moisture defic...

The Soil Moisture Dependence of TRMM Microwave Imager Rainfall Estimates

Science.gov (United States)

Seyyedi, H.; Anagnostou, E. N.

2011-12-01

This study presents an in-depth analysis of the dependence of overland rainfall estimates from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) on the soil moisture conditions at the land surface. TMI retrievals are verified against rainfall fields derived from a high resolution rain-gauge network (MESONET) covering Oklahoma. Soil moisture (SOM) patterns are extracted based on recorded data from 2000-2007 with 30 minutes temporal resolution. The area is divided into wet and dry regions based on normalized SOM (Nsom) values. Statistical comparison between two groups is conducted based on recorded ground station measurements and the corresponding passive microwave retrievals from TMI overpasses at the respective MESONET station location and time. The zero order error statistics show that the Probability of Detection (POD) for the wet regions (higher Nsom values) is higher than the dry regions. The Falls Alarm Ratio (FAR) and volumetric FAR is lower for the wet regions. The volumetric missed rain for the wet region is lower than dry region. Analysis of the MESONET-to-TMI ratio values shows that TMI tends to overestimate for surface rainfall intensities less than 12 (mm/h), however the magnitude of the overestimation over the wet regions is lower than the dry regions.

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)

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

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

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.

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

Effects of soil moisture on the diurnal pattern of pesticide emission: Comparison of simulations with field measurements

Science.gov (United States)

Reichman, Rivka; Yates, Scott R.; Skaggs, Todd H.; Rolston, Dennis E.

2013-02-01

Pesticide volatilization from agricultural soils is one of the main pathways in which pesticides are dispersed in the environment and affects ecosystems including human welfare. Thus, it is necessary to have accurate knowledge of the various physical and chemical mechanisms that affect volatilization rates from field soils. A verification of the influence of soil moisture modeling on the simulated volatilization rate, soil temperature and soil-water content is presented. Model simulations are compared with data collected in a field study that measured the effect of soil moisture on diazinon volatilization. These data included diurnal changes in volatilization rate, soil-water content, and soil temperature measured at two depths. The simulations were performed using a comprehensive non-isothermal model, two water retention functions, and two soil surface resistance functions, resulting in four tested models. Results show that the degree of similarity between volatilization curves simulated using the four models depended on the initial water content. Under fairly wet conditions, the simulated curves mainly differ in the magnitude of their deviation from the measured values. However, under intermediate and low moisture conditions, the simulated curves also differed in their pattern (shape). The model prediction accuracy depended on soil moisture. Under normal practices, where initial soil moisture is about field capacity or higher, a combination of Brooks and Corey water retention and the van de Grind and Owe soil surface resistance functions led to the most accurate predictions. However, under extremely dry conditions, when soil-water content in the top 1 cm is below the volumetric threshold value, the use of a full-range water retention function increased prediction accuracy. The different models did not affect the soil temperature predictions, and had a minor effect on the predicted soil-water content of Yolo silty clay soil.

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.

Using lagged dependence to identify (de)coupled surface and subsurface soil moisture values

Science.gov (United States)

Carranza, Coleen D. U.; van der Ploeg, Martine J.; Torfs, Paul J. J. F.

2018-04-01

Recent advances in radar remote sensing popularized the mapping of surface soil moisture at different spatial scales. Surface soil moisture measurements are used in combination with hydrological models to determine subsurface soil moisture values. However, variability of soil moisture across the soil column is important for estimating depth-integrated values, as decoupling between surface and subsurface can occur. In this study, we employ new methods to investigate the occurrence of (de)coupling between surface and subsurface soil moisture. Using time series datasets, lagged dependence was incorporated in assessing (de)coupling with the idea that surface soil moisture conditions will be reflected at the subsurface after a certain delay. The main approach involves the application of a distributed-lag nonlinear model (DLNM) to simultaneously represent both the functional relation and the lag structure in the time series. The results of an exploratory analysis using residuals from a fitted loess function serve as a posteriori information to determine (de)coupled values. Both methods allow for a range of (de)coupled soil moisture values to be quantified. Results provide new insights into the decoupled range as its occurrence among the sites investigated is not limited to dry conditions.

Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils

Science.gov (United States)

Bond-Lamberty, Ben; Smith, A. Peyton; Bailey, Vanessa

2016-12-01

Rapid climatic changes, rising air temperatures, and increased fires are expected to drive permafrost degradation and alter soil carbon (C) cycling in many high-latitude ecosystems. How these soils will respond to changes in their temperature, moisture, and overlying vegetation is uncertain but critical to understand given the large soil C stocks in these regions. We used a laboratory experiment to examine how temperature and moisture control CO2 and CH4 emissions from mineral soils sampled from the bottom of the annual active layer, i.e., directly above permafrost, in an Alaskan boreal forest. Gas emissions from 30 cores, subjected to two temperatures and either field moisture conditions or experimental drought, were tracked over a 100-day incubation; we also measured a variety of physical and chemical characteristics of the cores. Gravimetric water content was 0.31 ± 0.12 (unitless) at the beginning of the incubation; cores at field moisture were unchanged at the end, but drought cores had declined to 0.06 ± 0.04. Daily CO2 fluxes were positively correlated with incubation chamber temperature, core water content, and percent soil nitrogen. They also had a temperature sensitivity (Q10) of 1.3 and 1.9 for the field moisture and drought treatments, respectively. Daily CH4 emissions were most strongly correlated with percent nitrogen, but neither temperature nor water content was a significant first-order predictor of CH4 fluxes. The cumulative production of C from CO2 was over 6 orders of magnitude higher than that from CH4; cumulative CO2 was correlated with incubation temperature and moisture treatment, with drought cores producing 52-73 % lower C. Cumulative CH4 production was unaffected by any treatment. These results suggest that deep active-layer soils may be sensitive to changes in soil moisture under aerobic conditions, a critical factor as discontinuous permafrost thaws in interior Alaska. Deep but unfrozen high-latitude soils have been shown to be

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

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.

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.

Polymer Composite Rebars under Moisture and Mechanical Loading

Science.gov (United States)

Adam, Mohamed Ibrahim

Fiber reinforced polymer (FRP) composites have been increasingly used by the civil engineering construction industry in the past few years. Glass fiber reinforced polymer (GFRP) is one of the most commonly used FRP materials in applications such as a profile member or reinforcing rebars. Lightweight, high strength and excellent corrosion resistance are just a few among the many appealing properties of GFRP rebars. Use of GFRP has been focused on extending the service life of civil engineering structures acting as reinforcement instead of steel. FRP composites also provide opportunities for repair and retrofit of existing structures to extend their service life or to increase their load bearing capacity. However, the higher initial cost of GFRP rebar compared to steel is a current barrier in their widespread usage. Recent advancements in processes such as pultrusion have helped in reducing the cost of the FRP rebar. In addition, a higher initial raw material cost can be offset by the lower lifecycle cost of GFRP rebar compared to steel rebar. These factors are helping in increasing the acceptance of GFRP rebars in construction industry. Availability of technical data on GFRP, especially for long-term performance and under practical loading conditions faced in a real-life application, can help in increasing their acceptance. Although there have been numerous studies to characterize the properties of GFRP in terms of strength, corrosion, fatigue, chemical and physical aging, and natural weathering, most of these studies were limited to material characterization and were not intended for civil engineering applications. For this reason, and to encourage the increased use of GFRP rebars in concrete structures, GFRP rebar has been an important research topic in recent years. Of particular interest are their long-term durability and their susceptibility to degradation that might be initiated by moisture, temperature, and corrosive chemical environments. This is because

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.

Pre-sowing static magnetic field treatment for improving water and radiation use efficiency in chickpea (Cicer arietinum L.) under soil moisture stress.

Science.gov (United States)

Mridha, Nilimesh; Chattaraj, Sudipta; Chakraborty, Debashis; Anand, Anjali; Aggarwal, Pramila; Nagarajan, Shantha

2016-09-01

Soil moisture stress during pod filling is a major constraint in production of chickpea (Cicer arietinum L.), a fundamentally dry land crop. We investigated effect of pre-sowing seed priming with static magnetic field (SMF) on alleviation of stress through improvement in radiation and water use efficiencies. Experiments were conducted under greenhouse and open field conditions with desi and kabuli genotypes. Seeds exposed to SMF (strength: 100 mT, exposure: 1 h) led to increase in root volume and surface area by 70% and 65%, respectively. This enabled the crop to utilize 60% higher moisture during the active growth period (78-118 days after sowing), when soil moisture became limiting. Both genotypes from treated seeds had better water utilization, biomass, and radiation use efficiencies (17%, 40%, and 26% over control). Seed pre-treatment with SMF could, therefore, be a viable option for chickpea to alleviate soil moisture stress in arid and semi-arid regions, helping in augmenting its production. It could be a viable option to improve growth and yield of chickpea under deficit soil moisture condition, as the selection and breeding program takes a decade before a tolerant variety is released. Bioelectromagnetics. 37:400-408, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

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

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.

Mineralogical, textural and physical-mechanical study of hydraulic lime mortars cured under different moisture conditions

Directory of Open Access Journals (Sweden)

Arizzi, A.

2015-06-01

Full Text Available This work focuses on the chemical-mineralogical, textural and physical-mechanical properties of hydraulic lime mortars made with siliceous and calcareous aggregate. Mortars were cured at 60% and 90% of relative humidity, so as to assess the variability of mortar petrophysical properties in the hardened state due to the moisture conditions. The final aim was to determine the most adequate moisture conditions to be maintained during application and hardening of hydraulic mortars intended for repair interventions. We found out that using a calcareous aggregate and curing mortar at 90% of relative humidity give place to better textural and mechanical properties. However, these characteristics mostly depend on the maximum size of the aggregate grains, which should be smaller than 6 mm, in order to avoid the occurrence of mechanical discontinuities in the mortar.En este trabajo se han estudiado las propiedades químico-mineralógicas, texturales y físico-mecánicas de morteros de cal hidráulica elaborados con áridos silíceo y calcítico. Estos morteros se han curado al 60% y 90% de humedad relativa, con el fin de evaluar las eventuales diferencias en las propiedades petrofísicas de los morteros una vez endurecidos y así establecer cuál de los dos ambientes es recomendable durante la aplicación y fraguado de morteros de cal hidráulica destinados a obras de restauración. Se ha encontrado que el uso de un árido de composición calcítica y el curado al 90% de humedad relativa dan lugar a morteros hidráulicos con mejores características texturales y propiedades mecánicas. De todas formas, estas características dependen principalmente del tamaño máximo del árido empleado, que debería ser inferior a 6 mm para evitar discontinuidades mecánicas en el mortero.

Development and evaluation of the MTVDI for soil moisture monitoring

Science.gov (United States)

Zhu, Wenbin; Lv, Aifeng; Jia, Shaofeng; Sun, Liang

2017-06-01

Several parameterization schemes have been developed to retrieve the soil moisture information involved in the remotely sensed surface temperature-vegetation index (Ts - VI) space. However, most of them are performed with the constraint of the dry edge of the Ts - VI space to define the maximum water stressed conditions. In view of the subjectivity and uncertainty involved in the determination of the dry edge, a new index termed as the Modified Temperature-Vegetation Dryness Index (MTVDI) was developed in this paper to reduce the reliance of the parameterization scheme on the dry edge. In the parameterization scheme of MTVDI, isopleth lines of soil moisture involved in the feature space were retrieved by the temperature-vegetation index method, and only the maximum surface temperature of bare soil (Tsmax) was indispensable in the definition of maximum water stressed conditions. For evaluation purpose, the MTVDI was demonstrated in the Southern Great Plains region of the U.S. and was compared with two other traditional soil moisture indexes developed under the constraint of dry edge. The comparison confirmed the effectivity of the MTVDI in monitoring the spatial pattern and seasonal variation of soil moisture. Our analyses also suggest that Tsmax, the only parameter needed in the definition of maximum water stressed conditions, can be retrieved directly from the parameterization scheme itself. Therefore, the retrieval of MTVDI can be performed independent of the dry edge, which is a significant improvement to the traditional parameterization schemes of soil moisture from the Ts - VI feature space.

Effect of moisture stress and low phosphorus on yield of some ...

African Journals Online (AJOL)

Soybean genotypes belonging to different maturity periods were planted under normal, nutrient (P) and moisture stress conditions in a combined design with three replications. The objective was to determine the effect of phosphorus and moisture stress on yield and yield components of soybean in order to select varieties ...

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...

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.

Extreme fire events are related to previous-year surface moisture conditions in permafrost-underlain larch forests of Siberia

International Nuclear Information System (INIS)

Forkel, Matthias; Beer, Christian; Thonicke, Kirsten; Cramer, Wolfgang; Bartalev, Sergey; Schmullius, Christiane

2012-01-01

Wildfires are a natural and important element in the functioning of boreal forests. However, in some years, fires with extreme spread and severity occur. Such severe fires can degrade the forest, affect human values, emit huge amounts of carbon and aerosols and alter the land surface albedo. Usually, wind, slope and dry air conditions have been recognized as factors determining fire spread. Here we identify surface moisture as an additional important driving factor for the evolution of extreme fire events in the Baikal region. An area of 127 000 km 2 burned in this region in 2003, a large part of it in regions underlain by permafrost. Analyses of satellite data for 2002–2009 indicate that previous-summer surface moisture is a better predictor for burned area than precipitation anomalies or fire weather indices for larch forests with continuous permafrost. Our analysis advances the understanding of complex interactions between the atmosphere, vegetation and soil, and how coupled mechanisms can lead to extreme events. These findings emphasize the importance of a mechanistic coupling of soil thermodynamics, hydrology, vegetation functioning, and fire activity in Earth system models for projecting climate change impacts over the next century. (letter)

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.

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.

Moisture transport properties of brick – comparison of exposed, impregnated and rendered brick

DEFF Research Database (Denmark)

Hansen, Tessa Kvist; Bjarløv, Søren Peter; Peuhkuri, Ruut

2016-01-01

In regards to internal insulation of preservation worthy brick façades, external moisture sources, such as wind-driven rain exposure, inevitably has an impact on moisture conditions within the masonry construction. Surface treatments, such as hydrophobation or render, may remedy the impacts...... of external moisture. In the present paper the surface absorption of liquid water on masonry façades of untreated, hydrophobated and rendered brick, are determined experimentally and compared. The experimental work focuses on methods that can be applied on-site, Karsten tube measurements. These measurements...... are supplemented with results from laboratory measurements of water absorption coefficient by partial immersion. Based on obtained measurement results, simulations are made with external liquid water loads for determination of moisture conditions within the masonry of different surface treatments. Experimental...

Performance of diverse wheat genetic stocks under moisture stress condition

International Nuclear Information System (INIS)

Seher, M.; Shabbir, G.; Rasheed, A.

2015-01-01

This study was conducted to evaluate divergent wheat germplasm for their performance under drought and control conditions. The germplasm consists of wheat land races of Pakistan, advanced D-genome synthetic derivatives and high yielding varieties of Pakistan. This wide array of germplasm was selected to identify sources, which can be opted later by the wheat breeders while breeding for drought tolerance. The evaluation parameters involved some important physiochemical testing and morphological characteristics in the field under drought and control conditions. Based on these parameters, 13 wheat genotypes were selected on the basis of their best performance regarding morphological and physiological parameters. These genotypes exhibited higher yield under drought stress conditions and increased percentage of proline, sugar, SOD and protein content under laboratory conditions as compared to the susceptible genotypes. Correlation studies revealed that grains per spike (GPS) and thousand grain weight (TGW) had direct relationship with spike length (SL), proline and sugar content under both control and drought conditions. Thus, these parameters can be used as selection criteria for the identification of tolerant genotypes. (author)

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.

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

On the combined effect of moisture diffusion and cyclic pore pressure generation in asphalt concrete

NARCIS (Netherlands)

Varveri, A.; Scarpas, A.; Collop, A.; Erkens, S.M.J.G.

2014-01-01

In this paper, a new moisture conditioning protocol which attempts to distinguish the contributions of long- and short-term moisture damage, i.e. moisture diffusion and cyclic pore pressure generation, in asphalt mixtures is presented. The capability of the proposed protocol to rank various asphalt

Moisture meter calibrations for untreated and ACQ-treated southern yellow pine lumber and plywood

Science.gov (United States)

C.R. Boardman; Samuel V. Glass; Charles G. Carll

2011-01-01

This study investigates the effects of alkaline copper quaternary (ACQ) preservative treatment and of plywood glue lines on resistance-based moisture content (MC) measurements. Moisture meter readings using stainless steel screws as electrodes were acquired over a range of moisture conditions in Southern Yellow Pine (SYP) lumber and plywood. Calibration equations are...

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.

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

A Lagrangian analysis of the moisture budget over the Fertile Crescent during two intense drought episodes

Science.gov (United States)

Salah, Zeinab; Nieto, Raquel; Drumond, Anita; Gimeno, Luis; Vicente-Serrano, Sergio M.

2018-05-01

The Fertile Crescent (FC) region comprises the east coast of the Mediterranean Sea and the northern part of the Arabian Peninsula. The FC suffered two severe drought episodes separated by a 7-year period, in 1998-2000 and 2007-2009, which are considered the most severe episodes to hit the region in the last 50 years. A Lagrangian model (FLEXPART) and ERA-Interim data (with a 1° × 1° lat-long resolution) were used to identify for the first time the climatological sources of moisture for the FC and their characteristics. Variability and the source-receptor relationships, concerning their contribution to the precipitation, and the implications regarding the transport of moisture changes over the FC, during the wet season (October-May) from 1980 to 2014 were analysed. The main climatological moisture sources during this period were determined to be the FC itself, the eastern Mediterranean Sea, the Red Sea, the Persian Gulf, the Arabian Sea, the Caspian and Black Seas, and the central and western parts of the Mediterranean Sea. The analysis showed higher anomalous conditions in the moisture transport from some moisture sources during the two outstanding drought episodes. The key feature of the wet seasons during these episodes was a deficit in the moisture losses over the studied area related to the FC itself, the Red and Arabian Seas sources, followed and to a lesser extent by the eastern Mediterranean Sea over the northern part of the FC region. Nevertheless, the moisture supply deficit from the sources was much greater during the 2007-2009 drought event. The SPEI index at large scales (24 months) showed that the 2007-2009 episode was part of longer-term drought conditions that had been developing over the previous months, reinforcing the drought severity given recycling processes attributed to the FC. During the two extreme drought episodes, the mountainous terrain over the northern and eastern FC suffered the highest precipitation deficits, and these areas are

Measured temperature and moisture conditions in the roof attic of a one-and-a-half story house

DEFF Research Database (Denmark)

Nielsen, Anker; Morelli, Martin

2017-01-01

Temperature and moisture measurements were made in a ventilated attic on a house with 200 mm mineral wool insulation. The measurements showed that 1) solar radiation had a great effect on the temperature in the attic; 2) moisture content reached a level below the risk of mold formation – no mold ...

Dynamic Moisture Sorption and Desorption in Fumed Silica-filled Silicone Foam

Energy Technology Data Exchange (ETDEWEB)

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

2016-09-02

Characterizing dynamic moisture sorption and desorption in fumed silica-filled silicone foam is necessary for determining material compatibilities and life predictions, particularly in sealed environments that may be exposed to a range of environmental conditions. Thermogravimetric analysis (TGA) and near infrared spectroscopy (NIR) were performed on S5470 fumed silica-filled silicone foam to determine the weight percent of moisture at saturation. Additionally, TGA was used to determine the time, temperature, and relative humidity levels required for sorption and desorption of physisorbed moisture in S5470.

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.

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...

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.

Spatial Variation of Soil Type and Soil Moisture in the Regional Atmospheric Modeling System

Energy Technology Data Exchange (ETDEWEB)

Buckley, R.

2001-06-27

Soil characteristics (texture and moisture) are typically assumed to be initially constant when performing simulations with the Regional Atmospheric Modeling System (RAMS). Soil texture is spatially homogeneous and time-independent, while soil moisture is often spatially homogeneous initially, but time-dependent. This report discusses the conversion of a global data set of Food and Agriculture Organization (FAO) soil types to RAMS soil texture and the subsequent modifications required in RAMS to ingest this information. Spatial variations in initial soil moisture obtained from the National Center for Environmental Predictions (NCEP) large-scale models are also introduced. Comparisons involving simulations over the southeastern United States for two different time periods, one during warmer, more humid summer conditions, and one during cooler, dryer winter conditions, reveals differences in surface conditions related to increases or decreases in near-surface atmospheric moisture con tent as a result of different soil properties. Three separate simulation types were considered. The base case assumed spatially homogeneous soil texture and initial soil moisture. The second case assumed variable soil texture and constant initial soil moisture, while the third case allowed for both variable soil texture and initial soil moisture. The simulation domain was further divided into four geographically distinct regions. It is concluded there is a more dramatic impact on thermodynamic variables (surface temperature and dewpoint) than on surface winds, and a more pronounced variability in results during the summer period. While no obvious trends in surface winds or dewpoint temperature were found relative to observations covering all regions and times, improvement in surface temperatures in most regions and time periods was generally seen with the incorporation of variable soil texture and initial soil moisture.

Space-based passive microwave soil moisture retrievals and the correction for a dynamic open water fraction

Directory of Open Access Journals (Sweden)

B. T. Gouweleeuw

2012-06-01

Full Text Available The large observation footprint of low-frequency satellite microwave emissions complicates the interpretation of near-surface soil moisture retrievals. While the effect of sub-footprint lateral heterogeneity is relatively limited under unsaturated conditions, open water bodies (if not accounted for cause a strong positive bias in the satellite-derived soil moisture retrieval. This bias is generally assumed static and associated with large, continental lakes and coastal areas. Temporal changes in the extent of smaller water bodies as small as a few percent of the sensor footprint size, however, can cause significant and dynamic biases. We analysed the influence of such small open water bodies on near-surface soil moisture products derived from actual (non-synthetic data from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E for three areas in Oklahoma, USA. Differences between on-ground observations, model estimates and AMSR-E retrievals were related to dynamic estimates of open water fraction, one retrieved from a global daily record based on higher frequency AMSR-E data, a second derived from the Moderate Resolution Imaging Spectroradiometer (MODIS and a third through inversion of the radiative transfer model, used to retrieve soil moisture. The comparison demonstrates the presence of relatively small areas (<0.05 of open water in or near the sensor footprint, possibly in combination with increased, below-critical vegetation density conditions (optical density <0.8, which contribute to seasonally varying biases in excess of 0.2 (m³ m⁻³ soil water content. These errors need to be addressed, either through elimination or accurate characterisation, if the soil moisture retrievals are to be used effectively in a data assimilation scheme.

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...

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.

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.

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.

Microstructure and physicochemical properties reveal differences between high moisture buffalo and bovine Mozzarella cheeses.

Science.gov (United States)

Nguyen, Hanh T H; Ong, Lydia; Lopez, Christelle; Kentish, Sandra E; Gras, Sally L

2017-12-01

Mozzarella cheese is a classical dairy product but most research to date has focused on low moisture products. In this study, the microstructure and physicochemical properties of both laboratory and commercially produced high moisture buffalo Mozzarella cheeses were investigated and compared to high moisture bovine products. Buffalo and bovine Mozzarella cheeses were found to significantly differ in their microstructure, chemical composition, organic acid and proteolytic profiles but had similar hardness and meltability. The buffalo cheeses exhibited a significantly higher ratio of fat to protein and a microstructure containing larger fat patches and a less dense protein network. Liquid chromatography mass spectrometry detected the presence of only β-casein variant A2 and a single β-lactoglobulin variant in buffalo products compared to the presence of both β-casein variants A1 and A2 and β-lactoglobulin variants A and B in bovine cheese. These differences arise from the different milk composition and processing conditions. The differences in microstructure and physicochemical properties observed here offer a new approach to identify the sources of milk used in commercial cheese products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aspen increase soil moisture, nutrients, organic matter and respiration in Rocky Mountain forest communities.

Science.gov (United States)

Buck, Joshua R; St Clair, Samuel B

2012-01-01

Development and change in forest communities are strongly influenced by plant-soil interactions. The primary objective of this paper was to identify how forest soil characteristics vary along gradients of forest community composition in aspen-conifer forests to better understand the relationship between forest vegetation characteristics and soil processes. The study was conducted on the Fishlake National Forest, Utah, USA. Soil measurements were collected in adjacent forest stands that were characterized as aspen dominated, mixed, conifer dominated or open meadow, which includes the range of vegetation conditions that exist in seral aspen forests. Soil chemistry, moisture content, respiration, and temperature were measured. There was a consistent trend in which aspen stands demonstrated higher mean soil nutrient concentrations than mixed and conifer dominated stands and meadows. Specifically, total N, NO(3) and NH(4) were nearly two-fold higher in soil underneath aspen dominated stands. Soil moisture was significantly higher in aspen stands and meadows in early summer but converged to similar levels as those found in mixed and conifer dominated stands in late summer. Soil respiration was significantly higher in aspen stands than conifer stands or meadows throughout the summer. These results suggest that changes in disturbance regimes or climate scenarios that favor conifer expansion or loss of aspen will decrease soil resource availability, which is likely to have important feedbacks on plant community development.

Fuel optimization in a multi chamber incinerator by the moisture control of oily sludge and medical wastes

International Nuclear Information System (INIS)

Haider, I.; Hussain, S.; Khan, S.; Mehran, T.

2011-01-01

Experiments have been performed to study the effects of %age moisture content on fuel optimization during the waste feed combustion of oily sludge, medical waste and mix blend waste in a 50 kg/hr multi chamber incinerator installed at NCPC- ARL RWP. Intention is to find out the optimum and in compliance with NEQs incinerator performance at various moisture contents in the different waste feeds. Optimum performances of the incinerator, so that optimum operating moisture conditions, which has been used for multi purpose waste, feeds, may be defined. Three waste feeds of 10 kg batch size were used for the experimentation namely; Oily Sludge, Medical waste and Mix blend waste (oily sludge and medical), with the primary chamber preheating temperature 655 deg. C for 15 mins. interval monitoring. The secondary chamber temperature was set to 850 deg. C. By the data obtained it is apparent that rising the waste moisture content tend to increase fuel consumption specifically in case of medical waste and hence lowering the overall combustion efficiency. In the emissions the CO/sub 2/ concentration is showing the incineration efficiency. Higher efficiency of the system could have been achieved by increasing the CO/sub 2/ in the gases leaving the incinerator, lower fuel usage per kg waste feed and maintain proper operating conditions. Fuel consumption for the oily sludge with 10% moisture content, was found to be least as compared with the same %age of medical waste and mix blend waste. However environmental compliance of the operation is shown by the flue gas analysis. The results shows that using mix blend(oily sludge and medical) waste having 12-13% moisture content would be suitable for incineration in multi-chamber incinerator .Other makes it possible to determine the optimum incinerator temperature control settings and operating conditions, as well as to assure continuous, efficient, environmentally satisfactory operation. The optimum fuel consumption for 10 kg each waste

4.4 Development of a 30-Year Soil Moisture Climatology for Situational Awareness and Public Health Applications

Science.gov (United States)

Case, Jonathan L.; Zavodsky, Bradley T.; White, Kristopher D.; Bell, Jesse E.

2015-01-01

This paper provided a brief background on the work being done at NASA SPoRT and the CDC to create a soil moisture climatology over the CONUS at high spatial resolution, and to provide a valuable source of soil moisture information to the CDC for monitoring conditions that could favor the development of Valley Fever. The soil moisture climatology has multi-faceted applications for both the NOAA/NWS situational awareness in the areas of drought and flooding, and for the Public Health community. SPoRT plans to increase its interaction with the drought monitoring and Public Health communities by enhancing this testbed soil moisture anomaly product. This soil moisture climatology run will also serve as a foundation for upgrading the real-time (currently southeastern CONUS) SPoRT-LIS to a full CONUS domain based on LIS version 7 and incorporating real-time GVF data from the Suomi-NPP Visible Infrared Imaging Radiometer Suite (Vargas et al. 2013) into LIS-Noah. The upgraded SPoRT-LIS run will serve as a testbed proof-of-concept of a higher-resolution NLDAS-2 modeling member. The climatology run will be extended to near real-time using the NLDAS-2 meteorological forcing from 2011 to present. The fixed 1981-2010 climatology shall provide the soil moisture "normals" for the production of real-time soil moisture anomalies. SPoRT also envisions a web-mapping type of service in which an end-user could put in a request for either an historical or real-time soil moisture anomaly graph for a specified county (as exemplified by Figure 2) and/or for local and regional maps of soil moisture proxy percentiles. Finally, SPoRT seeks to assimilate satellite soil moisture data from the current Soil Moisture Ocean Salinity (SMOS; Blankenship et al. 2014) and the recently-launched NASA Soil Moisture Active Passive (SMAP; Entekhabi et al. 2010) missions, using the EnKF capability within LIS. The 9-km combined active radar and passive microwave retrieval product from SMAP (Das et al. 2011

The impact of cerium oxide nanoparticles on the physiology of soybean (Glycine max (L.) Merr.) under different soil moisture conditions.

Science.gov (United States)

Cao, Zhiming; Rossi, Lorenzo; Stowers, Cheyenne; Zhang, Weilan; Lombardini, Leonardo; Ma, Xingmao

2018-01-01

The ongoing global climate change raises concerns over the decreasing moisture content in agricultural soils. Our research investigated the physiological impact of two types of cerium oxide nanoparticles (CeO 2 NPs) on soybean at different moisture content levels. One CeO 2 NP was positively charged on the surface and the other negatively charged due to the polyvinylpyrrolidone (PVP) coating. The results suggest that the effect of CeO 2 NPs on plant photosynthesis and water use efficiency (WUE) was dependent upon the soil moisture content. Both types of CeO 2 NPs exhibited consistently positive impacts on plant photosynthesis at the moisture content above 70% of field capacity (θ fc ). Similar positive impact of CeO 2 NPs was not observed at 55% θ fc , suggesting that the physiological impact of CeO 2 NPs was dependent upon the soil moisture content. The results also revealed that V Cmax (maximum carboxylation rate) was affected by CeO 2 NPs, indicating that CeO 2 NPs affected the Rubisco activity which governs carbon assimilation in photosynthesis. In conclusion, CeO 2 NPs demonstrated significant impacts on the photosynthesis and WUE of soybeans and such impacts were affected by the soil moisture content. Graphical abstract Soil moisture content affects plant cerium oxide nanoparticle interactions.

Data Assimilation using observed streamflow and remotely-sensed soil moisture for improving sub-seasonal-to-seasonal forecasting

Science.gov (United States)

Arumugam, S.; Mazrooei, A.; Lakshmi, V.; Wood, A.

2017-12-01

Subseasonal-to-seasonal (S2S) forecasts of soil moisture and streamflow provides critical information for water and agricultural systems to support short-term planning and mangement. This study evaluates the role of observed streamflow and remotely-sensed soil moisture from SMAP (Soil Moisture Active Passive) mission in improving S2S streamflow and soil moisture forecasting using data assimilation (DA). We first show the ability to forecast soil moisture at monthly-to-seaasonal time scale by forcing climate forecasts with NASA's Land Information System and then compares the developed soil moisture forecast with the SMAP data over the Southeast US. Our analyses show significant skill in forecasting real-time soil moisture over 1-3 months using climate information. We also show that the developed soil moisture forecasts capture the observed severe drought conditions (2007-2008) over the Southeast US. Following that, we consider both SMAP data and observed streamflow for improving S2S streamflow and soil moisture forecasts for a pilot study area, Tar River basin, in NC. Towards this, we consider variational assimilation (VAR) of gauge-measured daily streamflow data in improving initial hydrologic conditions of Variable Infiltration Capacity (VIC) model. The utility of data assimilation is then assessed in improving S2S forecasts of streamflow and soil moisture through a retrospective analyses. Furthermore, the optimal frequency of data assimilation and optimal analysis window (number of past observations to use) are also assessed in order to achieve the maximum improvement in S2S forecasts of streamflow and soil moisture. Potential utility of updating initial conditions using DA and providing skillful forcings are also discussed.

Sensitivity of convective precipitation to soil moisture and vegetation during break spell of Indian summer monsoon

Science.gov (United States)

Kutty, Govindan; Sandeep, S.; Vinodkumar; Nhaloor, Sreejith

2017-07-01

Indian summer monsoon rainfall is characterized by large intra-seasonal fluctuations in the form of active and break spells in rainfall. This study investigates the role of soil moisture and vegetation on 30-h precipitation forecasts during the break monsoon period using Weather Research and Forecast (WRF) model. The working hypothesis is that reduced rainfall, clear skies, and wet soil condition during the break monsoon period enhance land-atmosphere coupling over central India. Sensitivity experiments are conducted with modified initial soil moisture and vegetation. The results suggest that an increase in antecedent soil moisture would lead to an increase in precipitation, in general. The precipitation over the core monsoon region has increased by enhancing forest cover in the model simulations. Parameters such as Lifting Condensation Level, Level of Free Convection, and Convective Available Potential Energy indicate favorable atmospheric conditions for convection over forests, when wet soil conditions prevail. On spatial scales, the precipitation is more sensitive to soil moisture conditions over northeastern parts of India. Strong horizontal gradient in soil moisture and orographic uplift along the upslopes of Himalaya enhanced rainfall over the east of Indian subcontinent.

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.

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

Science.gov (United States)

Dedesko, Sandra; Siegel, Jeffrey A

2015-12-08

/or species, temperature, and nutrient availability. Despite these complexities, meaningful measurements can still be made to inform fungal growth by making localised, long-term, and continuous measurements of surface moisture. Such an approach will capture variations in a material's surface moisture, which could provide insight on a number of conditions that could lead to fungal proliferation.

Seedling establishment and physiological responses to temporal and spatial soil moisture changes

Science.gov (United States)

Jeremy Pinto; John D. Marshall; Kas Dumroese; Anthony S. Davis; Douglas R. Cobos

2016-01-01

In many forests of the world, the summer season (temporal element) brings drought conditions causing low soil moisture in the upper soil profile (spatial element) - a potentially large barrier to seedling establishment. We evaluated the relationship between initial seedling root depth, temporal and spatial changes in soil moisture during drought after...

[Response of mineralization of dissolved organic carbon to soil moisture in paddy and upland soils in hilly red soil region].

Science.gov (United States)

Chen, Xiang-Bi; Wang, Ai-Hua; Hu, Le-Ning; Huang, Yuan; Li, Yang; He, Xun-Yang; Su, Yi-Rong

2014-03-01

Typical paddy and upland soils were collected from a hilly subtropical red-soil region. 14C-labeled dissolved organic carbon (14C-DOC) was extracted from the paddy and upland soils incorporated with 14C-labeled straw after a 30-day (d) incubation period under simulated field conditions. A 100-d incubation experiment (25 degrees C) with the addition of 14C-DOC to paddy and upland soils was conducted to monitor the dynamics of 14C-DOC mineralization under different soil moisture conditions [45%, 60%, 75%, 90%, and 105% of the field water holding capacity (WHC)]. The results showed that after 100 days, 28.7%-61.4% of the labeled DOC in the two types of soils was mineralized to CO2. The mineralization rates of DOC in the paddy soils were significantly higher than in the upland soils under all soil moisture conditions, owing to the less complex composition of DOC in the paddy soils. The aerobic condition was beneficial for DOC mineralization in both soils, and the anaerobic condition was beneficial for DOC accumulation. The biodegradability and the proportion of the labile fraction of the added DOC increased with the increase of soil moisture (45% -90% WHC). Within 100 days, the labile DOC fraction accounted for 80.5%-91.1% (paddy soil) and 66.3%-72.4% (upland soil) of the cumulative mineralization of DOC, implying that the biodegradation rate of DOC was controlled by the percentage of labile DOC fraction.

Soil moisture trends in the Czech Republic between 1961 and 2012

Science.gov (United States)

Hlavinka, Petr; Trnka, Miroslav; Brázdil, Rudolf; Možný, Martin; Štěpánek, Petr; Dobrovolný, Petr; Zahradníček, Pavel; Balek, Jan; Semerádová, Daniela; Dubrovský, Martin; Eitzinger, Josef; Wardlow, Brian; Svoboda, Mark; Hayes, Michael; Žalud, Zdeněk

2015-04-01

Central Europe is generally not considered a drought-prone region, and the drought research and support is traditionally focused on the Mediterranean and southeastern part of the continent and drying trends there. However, Central Europe, including the Czech Republic, recently experienced a series of drought events with substantial impacts, especially on crop production. Because agriculture systems, and vegetation in general, have adapted to evenly distributed precipitation, the region is susceptible to even short-term droughts. The recent drought events may be the result of multi-decadal climate variability or a more general trend, with some studies showing a link to a more frequent occurrence of atmospheric circulation patterns that are conducive to drought. This study introduces an innovation to the standard methodological approaches in evaluating drought climatology by analyzing soil moisture conditions over more than fifty years. This approach relies on state-of-the art observed weather data and tested soil moisture model, and focuses on the dynamic simulation of soil moisture content with high temporal (daily) and spatial (500 m) resolution in a diverse landscape. Statistically significant trends of decreasing soil moisture content were found, notably during May and June between 1961 and 2012. In contrast, trends toward higher soil moisture content were noted during the October-March time period. When the periods of 2001-2012 and 1961-1980 were compared, the probability of drought between April and June was found to increase by 50%. This indicates a loading of the "climate dice" toward drier conditions. The probability of extreme drought events has been also found to increase. These results support the concerns about the potentially increased severity of drought events in Central Europe under projected climate change and has been submitted to International Journal of Climatology. The study was funded by project "Establishment of International Scientific Team

The impact of the uncertainty in the initial soil moisture condition of irrigated areas on the spatiotemporal characteristics of convective activity in Central Greece

Science.gov (United States)

Kotsopoulos, Stylianos; Ioannis, Tegoulias; Ioannis, Pytharoulis; Stergios, Kartsios; Dimitrios, Bampzelis; Theodore, Karacostas

2015-04-01

The region of Thessaly is the second largest plain in Greece and has a vital role in the financial life of the country, because of its significant agricultural production. The intensive and extensive cultivation of irrigated crops, in combination with the population increase and the alteration of precipitation patterns due to climate change, often leading the region to experience severe drought conditions, especially during the warm period of the year. The aim of the DAPHNE project is to tackle the problem of drought in this area by means of Weather Modification.In the framework of the project DAPHNE, the numerical weather prediction model WRF-ARW 3.5.1 is used to provide operational forecasts and hindcasts for the region of Thessaly. The goal of this study is to investigate the impact of the uncertainty in the initial soil moisture condition of irrigated areas, on the spatiotemporal characteristics of convective activity in the region of interest. To this end, six cases under the six most frequent synoptic conditions, which are associated with convective activity in the region of interest, are utilized, considering six different soil moisture initialization scenarios. In the first scenario (Control Run), the model is initialized with the surface soil moisture of the ECMWF analysis data, that usually does not take into account the modification of soil moisture due to agricultural activity in the area of interest. In the other five scenarios (Experiment 1,2,3,4,5) the soil moisture in the upper soil layers of the study area are modified from -50% to 50% of field capacity (-50%FC, -25%FC, FC, 25%FC, 50%FC),for the irrigated cropland.Three model domains, covering Europe, the Mediterranean Sea and northern Africa (d01), the wider area of Greece (d02) and central Greece - Thessaly region (d03) are used at horizontal grid-spacings of 15km, 5km and 1km respectively. ECMWF operational analyses at 6-hourly intervals (0.25ox0.25o lat.-long.) are imported as initial and

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)

Nuclear radiation moisture gauge calibration standard

International Nuclear Information System (INIS)

Berry, R.L.

1981-01-01

A hydrophobic standard for calibrating radiation moisture gauges is described. This standard has little or no affinity for water and accordingly will not take up or give off water under ambient conditions of fluctuating humidity in such a manner as to change the hydrogen content presented to a nuclear gauge undergoing calibration. (O.T.)

The effect of regional-scale soil-moisture deficits on mesoscale atmospheric dynamics that influence fire severity

Energy Technology Data Exchange (ETDEWEB)

Fast, J.D.

1994-09-30

This study employs a three-dimensional, nonhydrostatic mesoscale model to evaluate the effects of horizontally heterogeneous soil moisture and vegetation type on the atmosphere during two periods in which wildland fires occurred. Numerical sensitivity simulations demonstrate that evapotranspiration significantly affects the boundary-layer structure embedded in the synoptic-scale circulations. In regions with sufficiently moist soils, evapotranspiration increases the humidity and modifies the diurnally varying temperature near the surface. Occasionally, changes in the humidity and temperature fields can also be seen a significant distance downwind of the moist soil regions. The perturbations in the temperature fields ultimately affect the wind speed and direction over or at the boundaries of the moist-soil regions, but only at certain times during the simulation period. The higher humidity also increases the cloudiness and changes the precipitation amounts, indicating that soil moisture and vegetation may play an important role in modifying the spatial distribution and intensity of precipitation. A lower atmospheric stability index, that is an indicator of the potential for wildland fire, is also calculated from the model results. This index is also sensitive to the horizontal distribution of soil moisture and vegetation, especially in regions with relatively moist soils. While only two periods are examined in this study, the impact of surface inhomogeneities in soil moisture and vegetation type on the atmosphere is expected to be highly dependent on the particular synoptic conditions and upon the distribution of soil moisture.

Effects of storage structures and moisture contents on seed quality attributes of quality protein maize

Directory of Open Access Journals (Sweden)

Gopal Bhandari

2017-12-01

Full Text Available The study was aimed to examine the effects of various storage structures and moisture contents on seed quality attributes of quality protein maize seed. The quality protein maize (QPM-1 seed was tested in conventional seed storage containers (Fertilizer sack and earthen pot and the improved hermetic ones (Metal bin, Super grain bag, and Purdue Improved Crop Storage (PICS bag at Seed Science and Technology Division, Khumaltar, Nepal during February, 2015 to January 2016. Ten treatments comprising 5 storage devices in two moisture regimes (11% and 9% replicated thrice and laid out in Completely Randomized Design (CRD. Data on temperature, relative humidity (RH, germination, electrical conductivity (EC, seed moisture content (MC were collected bimonthly. The conventional containers were found liable to the external environmental condition whereas the hermetic structures observed with controlled RH level below 40% in all combinations. Electrical conductivity (EC for seed vigor showed that hermetic containers provide higher seed vigor than the conventional ones. Up to 4 months all treatments were found statistically at par for germination. A significant difference was observed in each treatment after 4 months where PICS bag & Super grain bag showed best germination followed by metal bin while fertilizer bag & earthen-pot showed poorer and poorest germination respectively till one year. Almost all treatments with lower MC showed better results than the treatments with higher MC. A negative correlation (R2=69.7% was found between EC and Germination. All six figures from 2 to 12 months on MC showed statistically different where hermetic plastic bags were found maintaining MC as initial whereas MC of fertilizer bags and earthen pot was spiked than the basal figure. The finding evidenced that the hermetic containers and low MC are the seed storage approaches for retaining the quality of seed even in an ambient environmental condition for more than a year.

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.

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.

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.

Comparison of time domain reflectometry, capacitance methods and neutron scattering in soil moisture measurements

International Nuclear Information System (INIS)

Khorasani, A.; Mousavi Shalmani, M. A.; Piervali Bieranvand, N.

2011-01-01

An accurate, precise, fast and ease as well as the ability for measurements in depth are the characteristics that are desirable in measuring soil moisture methods. To compare methods (time domain reflectometry and capacitance) with neutron scattering for soil water monitoring, an experiment was carried out in a randomized complete block design (Split Split plot) on tomato with three replications on the experimental field of International Atomic Energy Agency (Seibersdorf-Austria). The treatment instruments for the soil moisture monitoring (main factor) consist of neutron gauge, Diviner 2000, time domain reflectometer and an EnviroScan and different irrigation systems (first sub factor) consist of trickle and furrow irrigations and different depths of soil (second sub factor) consist of 0-20, 20-40 and 40-60 cm. The results showed that for the neutron gauge and time domain reflectometer the amount of soil moisture in both of trickle and furrow irrigations were the same, but the significant differences were recorded in Diviner 2000 and EnviroScan measurements. The results of this study showed that the neutron gauge is an acceptable and reliable means with the modern technology, with a precision of ±2 mm in 450 mm soil water to a depth of 1.5 meter and can be considered as the most practical method for measuring soil moisture profiles and irrigation planning program. The time domain reflectometer method in most mineral soils, without the need for calibration, with an accuracy ±0.01m 3 m -3 has a good performance in soil moisture and electrical conductivity measurements. The Diviner 2000 and EnviroScan are not well suitable for the above conditions for several reasons such as much higher soil moisture and a large error measurement and also its sensitivity to the soil gap and to the small change in the soil moisture in comparison with the neutron gauge and the time domain reflectometer methods.

Impact of Direct Soil Moisture and Revised Soil Moisture Index Methods on Hydrologic Predictions in an Arid Climate

Directory of Open Access Journals (Sweden)

Milad Jajarmizadeh

2014-01-01

Full Text Available The soil and water assessment tool (SWAT is a physically based model that is used extensively to simulate hydrologic processes in a wide range of climates around the world. SWAT uses spatial hydrometeorological data to simulate runoff through the computation of a retention curve number. The objective of the present study was to compare the performance of two approaches used for the calculation of curve numbers in SWAT, that is, the Revised Soil Moisture Index (SMI, which is based on previous meteorological conditions, and the Soil Moisture Condition II (SMCII, which is based on soil features for the prediction of flow. The results showed that the sensitive parameters for the SMI method are land-use and land-cover features. However, for the SMCII method, the soil and the channel are the sensitive parameters. The performances of the SMI and SMCII methods were analyzed using various indices. We concluded that the fair performance of the SMI method in an arid region may be due to the inherent characteristics of the method since it relies mostly on previous meteorological conditions and does not account for the soil features of the catchment.

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.

Vis-NIR hyperspectral imaging and multivariate analysis for prediction of the moisture content and hardness of Pistachio kernels roasted in different conditions

Directory of Open Access Journals (Sweden)

T Mohammadi Moghaddam

2015-09-01

Full Text Available Introduction: Pistachio nut is one of the most delicious and nutritious nuts in the world and it is being used as a salted and roasted product or as an ingredient in snacks, ice cream, desserts, etc. (Maghsudi, 2010; Kashaninejad et al. 2006. Roasting is one of the most important food processes which provides useful attributes to the product. One of the objectives of nut roasting is to alter and significantly enhance the flavor, texture, color and appearance of the product (Ozdemir, 2001. In recent years, spectral imaging techniques (i.e. hyperspectral and multispectral imaging have emerged as powerful tools for safequality inspection of various agricultural commodities (Gowen et al., 2007. The objectives of this study were to apply reflectance hyperspectral imaging for non-destructive determination of moisture content and hardness of pistachio kernels roasted in different conditions. Materials and methods: Dried O’hadi pistachio nuts were supplied from a local market in Mashhad. Pistachio nuts were soaked in 5L of 20% salt solution for 20min (Goktas Seyhan, 2003. For roasting process, three temperatures (90, 120 and 150°C, three times (20, 35 and 50 min and three air velocities (0.5, 1.5 and 2.5 m s-1 were applied. The moisture content of pistachio kernels was measured in triplicate using oven drying (3 gr samples at 105 °C for 12 hours. Uniaxial compression test by a 35mm diameter plastic cylinder, was made on the pistachio kernels, which were mounted on a platform. Samples were compressed at a depth of 2mm and speed of 30 mm min-1. A hyperspectral imaging system in the Vis-NIR range (400-1000 nm was employed. The spectral pre-processing techniques: first derivative and second derivative, median filter, Savitzkye-Golay, wavelet, multiplicative scatter correction (MSC and standard normal variate transformation (SNV were used. To make models at PLSR and ANN methods, ParLeS software and Matlab R2009a were used, respectively. The coefficient

Consumer Preferences, Product Characteristics, and Potentially Allergenic Ingredients in Best-selling Moisturizers.

Science.gov (United States)

Xu, Shuai; Kwa, Michael; Lohman, Mary E; Evers-Meltzer, Rachel; Silverberg, Jonathan I

2017-11-01

Because moisturizer use is critical for the prevention and treatment of numerous dermatological conditions, patients frequently request product recommendations from dermatologists. To determine the product performance characteristics and ingredients of best-selling moisturizers. This cohort study involved publicly available data of the top 100 best-selling whole-body moisturizing products at 3 major online retailers (Amazon, Target, and Walmart). Products marketed for use on a specific body part (eg, face, hands, eyelids) were excluded. Pairwise comparisons of median price per ounce on the basis of marketing claims (eg, dermatologist recommended, fragrance free, hypoallergenic) and presence of ingredients represented in the North American Contact Dermatitis Group (NACDG) series were conducted using Wilcoxon rank sum tests. The effect of vehicle type (eg, ointment, lotion, cream, butter) was assessed using the Kruskal-Wallis test. Cross-reactors and botanicals for fragrances were derived from the American Contact Dermatitis Society's Contact Allergen Management Program database. A total of 174 unique best-selling moisturizer products were identified, constituting 109 713 reviews as of August 2016. The median price per ounce was $0.59 (range, $0.10-$9.51 per ounce) with a wide range (9400%). The most popular vehicles were lotions (102 [59%]), followed by creams (22 [13%]), oils (21 [12%]), butters (14 [8%]), and ointments (3 [2%]). Only 12% (n = 21) of best-selling moisturizer products were free of NACDG allergens. The 3 most common allergens were fragrance mix (n = 87), paraben mix (n = 75), and tocopherol (n = 74). Products with the claim "dermatologist recommended" had higher median price per ounce ($0.79; interquartile range [IQR], $0.56-$1.27) than products without the claim ($0.59; IQR, $0.34-$0.92). Products with the claim "phthalate free" had higher median price per ounce ($1.38; IQR, $0.86-$1.63) than products without the claim ($0.59; IQR

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

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.

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.

Effect of soil-moisture stress on nitrogen uptake and fixation by plants

International Nuclear Information System (INIS)

Mitrosuhardjo, M.M.

1983-01-01

The effect of four levels of soil moisture, namely 25, 30, 35, and 40% (g/g) on nitrogen uptake and fixation by plants was studied in a greenhouse experiment. Soybean and wheat were used in this experiment. Both crops were grown in pots containing 7 kg loamy alluvial soil. Rhizobium japonicum was used as an inoculant for soybean, one week after planting. Nitrogen-15 labelled urea with 10% atom excess was applied to each pot with a dose rate of 70 mg N/pot (20 kg N/ha) two weeks after planting. Soil moisture was regularly controlled with porous-cup mercury tensiometers, and the amount of water consumed by plants was always recorded. Water was applied to each pot with a distribution pipe which was laid down in the centre of the soil depth, horizontally in a circular form, and was connected with a smaller pipe to the soil surface. The result obtained showed that the amount of water consumed by plants grown in a higher level of soil moisture was increased until soil aeration problems arose. A different amount of water consumption between soybean and wheat was observed at least until a certain period of growing time. Fertilizer nitrogen taken up by both crops varied with the different levels of soil moisture. Generally, greater fertilizer nitrogen was taken up by both crops grown in a higher level of soil moisture. The symbiotic fixation of nitrogen was reasonable, although no clarification has been found about the role of the four levels of soil-moisture treatment on it. A similar effect of soil-moisture stress on nodule dry matter and acetylene reduction was found. (author)

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

Influence of the convective surface transfer coefficients on the Heat, Air, and Moisture (HAM) building performance

DEFF Research Database (Denmark)

Steskens, Paul Wilhelmus Maria Hermanus; Janssen, Hans; Rode, Carsten

2009-01-01

Current models to predict heat, air and moisture (HAM) conditions in buildings assume constant boundary conditions for the temperature and relative humidity of the neighbouring air and for the surface heat and moisture transfer coefficients. These assumptions may introduce errors in the predicted...... influence on the predicted hygrothermal conditions at the surface of a building component and on the heat and vapour exchange with the indoor environment....

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.

Relative skills of soil moisture and vegetation optical depth retrievals for agricultural drought monitoring

Science.gov (United States)

Soil moisture condition is an important indicator for agricultural drought monitoring. Through the Land Parameter Retrieval Model (LPRM), vegetation optical depth (VOD) as well as surface soil moisture (SM) can be retrieved simultaneously from brightness temperature observations from the Advanced Mi...

SMAP Multi-Temporal Soil Moisture and Vegetation Optical Depth Retrievals in Vegetated Regions Including Higher-Order Soil-Canopy Interactions

Science.gov (United States)

Feldman, A.; Akbar, R.; Konings, A. G.; Piles, M.; Entekhabi, D.

2017-12-01

The Soil Moisture Active Passive (SMAP) mission utilizes a zeroth order radiative transfer model, known as the tau-omega model, to retrieve soil moisture from microwave brightness temperature observations. This model neglects first order scattering which is significant at L-Band in vegetated regions, or 30% of land cover. Previous higher order algorithms require extensive in-situ measurements and characterization of canopy layer physical properties. We propose a first order retrieval algorithm that approximately characterizes the eight first order emission pathways using rough surface reflectivity, vegetation optical depth (VOD), and scattering albedo terms. The recently developed Multi-Temporal Dual Channel Algorithm (MT-DCA) then retrieves these three parameters in a forward model without ancillary information under the assumption of temporally static albedo and constant vegetation water content between three day SMAP revisits. The approximated scattering terms are determined to be conservative estimates of analytically derived first order scattering terms. In addition, we find the first order algorithm to be more sensitive to surface emission than the tau-omega model. The simultaneously retrieved VOD, previously demonstrated to be proportional to vegetation water content, can provide insight into vegetation dynamics in regions with significant phenology. Specifically, dry tropical forests exhibit an increase in VOD during the dry season in alignment with prior studies that suggest that certain vegetative species green up during the dry season despite limited water availability. VOD retrieved using the first order algorithm and MT-DCA framework can therefore contribute to understanding of tropical forests' role in the carbon, energy, and water cycles, which has yet to be fully explained.

Technique for mass-spectrometric determination of moisture content in fuel elements and fuel element claddings

International Nuclear Information System (INIS)

Kurillovich, A.N.; Pimonov, Yu.I.; Biryukov, A.S.

1988-01-01

A technique for mass-spectroimetric determination of moisture content in fuel elements and fuek claddings in the 2x10 -4 -1.5x10 -2 g range is developed. The relative standard deviation is 0.13. A character of moisture extraction from oxide uranium fuels in the 20-700 deg C temperature range is studied. Approximately 80% of moisture is extracted from the fuels at 300 deg C. The moisture content in fuel elements with granular uranium oxide fuels is measured. Dependence of fuel element moisture content on conditions of hot vacuum drying is shown. The technique permits to optimize the fuel element fabrication process to decrease the moisture content in them. 4 refs.; 3 figs.; 2 tabs

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)

Western US high June 2015 temperatures and their relation to global warming and soil moisture

Science.gov (United States)

Philip, Sjoukje Y.; Kew, Sarah F.; Hauser, Mathias; Guillod, Benoit P.; Teuling, Adriaan J.; Whan, Kirien; Uhe, Peter; Oldenborgh, Geert Jan van

2018-04-01

The Western US states Washington (WA), Oregon (OR) and California (CA) experienced extremely high temperatures in June 2015. The temperature anomalies were so extreme that they cannot be explained with global warming alone. We investigate the hypothesis that soil moisture played an important role as well. We use a land surface model and a large ensemble from the weather@home modelling effort to investigate the coupling between soil moisture and temperature in a warming world. Both models show that May was anomalously dry, satisfying a prerequisite for the extreme heat wave, and they indicate that WA and OR are in a wet-to-dry transitional soil moisture regime. We use two different land surface-atmosphere coupling metrics to show that there was strong coupling between temperature, latent heat flux and the effect of soil moisture deficits on the energy balance in June 2015 in WA and OR. June temperature anomalies conditioned on wet/dry conditions show that both the mean and extreme temperatures become hotter for dry soils, especially in WA and OR. Fitting a Gaussian model to temperatures using soil moisture as a covariate shows that the June 2015 temperature values fit well in the extrapolated empirical temperature/drought lines. The high temperature anomalies in WA and OR are thus to be expected, given the dry soil moisture conditions and that those regions are in the transition from a wet to a dry regime. CA is already in the dry regime and therefore the necessity of taking soil moisture into account is of lower importance.

Seasonal moisture fluctuations four species of pocosin vegetation

Science.gov (United States)

George W. Wendel; Theodore G. Storey

1962-01-01

During the most severe burning conditions practically all of the living understory vegetation on pocosins may be consumed by fire (9). Even under less severe conditions leaves and branch tips are readily consumed. Whether the moisture content in the living vegetation is high, as it is in the spring, or low, as in the winter, exerts a strong influence on fuel...

Assessing the effect of soil use changes on soil moisture regimes in mountain regions. (Catalan Pre-Pyrenees NE Spain)

International Nuclear Information System (INIS)

Loaiza Usuga, Juan Carlos; Jarauta Bragulat, Eusebio; Porta Casanellas, Jaume; Poch Claret, Rosa Maria

2010-01-01

Soil moisture regimes under different land uses were observed and modeled in a representative forest basin in the Catalonian Pre-Pyrenees, more specifically in the Ribera Salada catchment (222.5 km2). The vegetation cover in the catchment consists of pasture, tillage and forest. A number of representative plots for each of these land cover types were intensely monitored during the study period. The annual precipitation fluctuates between 516 and 753 mm, while the soil moisture content oscillates between 14 and 26% in the middle and low lying areas of the basin, and between 21 and 48% in shady zones near the river bed, and in the higher parts of the basin. Soil moisture and rainfall are controlled firstly by altitude, with the existence of two climatic types in the basin (sub-Mediterranean and sub-alpine), and further, by land use. Two models were applied to the estimated water moisture regimes: the Jarauta Simulation Newhall model (JSM) and the Newhall simulation model (NSM) were found to be able to predict the soil moisture regimes in the basin in the different combinations of local abiotic and biotic factors. The JSM results are more precise than the results obtained using another frequently used method, more specifically the Newhall Simulation Model (NSM), which has been developed to simulate soil moisture regimes. NSM was found to overestimate wet soil moisture regimes. The results show the importance of the moisture control section size and Available Water Capacity (AWC) of the profile, in the moisture section control state and variability. The mountain soils are dominated by rustic and occasionally xeric regimes. Land use changes leading to an increase in forest areas would imply drier soil conditions and therefore drier soil water regimes. These effects are most evident in degraded shallow and stony soils with low AWC.

Influence of moisture absorption on properties of fiber reinforced polyamide 6 composites

DEFF Research Database (Denmark)

Raghavalu Thirumalai, Durai Prabhakaran; Løgstrup Andersen, Tom; Lystrup, Aage

2011-01-01

sensitive to moisture, and if PA6 is used as matrix material in a fiber composite, the properties of the fiber composite will depend on the moisture content of the material. At standard condition (23 °C and 50% RH) polyamide6 absorbs about 3 weight-% of water, whereas the PA6 material is dry right after...

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...

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....

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.

Moisture Durability Assessment of Selected Well-insulated Wall Assemblies

Energy Technology Data Exchange (ETDEWEB)

Pallin, Simon B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Boudreaux, Philip R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kehrer, Manfred [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hun, Diana E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jackson, Roderick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Desjarlais, Andre Omer [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-12-01

This report presents the results from studying the hygrothermal performance of two well-insulated wall assemblies, both complying with and exceeding international building codes (IECC 2015 2014, IRC 2015). The hygrothermal performance of walls is affected by a large number of influential parameters (e.g., outdoor and indoor climates, workmanship, material properties). This study was based on a probabilistic risk assessment in which a number of these influential parameters were simulated with their natural variability. The purpose of this approach was to generate simulation results based on laboratory chamber measurements that represent a variety of performances and thus better mimic realistic conditions. In total, laboratory measurements and 6,000 simulations were completed for five different US climate zones. A mold growth indicator (MGI) was used to estimate the risk of mold which potentially can cause moisture durability problems in the selected wall assemblies. Analyzing the possible impact on the indoor climate due to mold was not part of this study. The following conclusions can be reached from analyzing the simulation results. In a hot-humid climate, a higher R-value increases the importance of the airtightness because interior wall materials are at lower temperatures. In a cold climate, indoor humidity levels increase with increased airtightness. Air leakage must be considered in a hygrothermal risk assessment, since air efficiently brings moisture into buildings from either the interior or exterior environment. The sensitivity analysis of this study identifies mitigation strategies. Again, it is important to remark that MGI is an indicator of mold, not an indicator of indoor air quality and that mold is the most conservative indicator for moisture durability issues.

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...

The impact of non-isothermal soil moisture transport on evaporation fluxes in a maize cropland

Science.gov (United States)

Shao, Wei; Coenders-Gerrits, Miriam; Judge, Jasmeet; Zeng, Yijian; Su, Ye

2018-06-01

The process of evaporation interacts with the soil, which has various comprehensive mechanisms. Multiphase flow models solve air, vapour, water, and heat transport equations to simulate non-isothermal soil moisture transport of both liquid water and vapor flow, but are only applied in non-vegetated soils. For (sparsely) vegetated soils often energy balance models are used, however these lack the detailed information on non-isothermal soil moisture transport. In this study we coupled a multiphase flow model with a two-layer energy balance model to study the impact of non-isothermal soil moisture transport on evaporation fluxes (i.e., interception, transpiration, and soil evaporation) for vegetated soils. The proposed model was implemented at an experimental agricultural site in Florida, US, covering an entire maize-growing season (67 days). As the crops grew, transpiration and interception became gradually dominated, while the fraction of soil evaporation dropped from 100% to less than 20%. The mechanisms of soil evaporation vary depending on the soil moisture content. After precipitation the soil moisture content increased, exfiltration of the liquid water flow could transport sufficient water to sustain evaporation from soil, and the soil vapor transport was not significant. However, after a sufficient dry-down period, the soil moisture content significantly reduced, and the soil vapour flow significantly contributed to the upward moisture transport in topmost soil. A sensitivity analysis found that the simulations of moisture content and temperature at the soil surface varied substantially when including the advective (i.e., advection and mechanical dispersion) vapour transport in simulation, including the mechanism of advective vapour transport decreased soil evaporation rate under wet condition, while vice versa under dry condition. The results showed that the formulation of advective soil vapor transport in a soil-vegetation-atmosphere transfer continuum can

Influences of gas stream conditions on efficiency of tritiated moisture collection with P2O5-desiccant and isotope effect

International Nuclear Information System (INIS)

Kotoh, Kenji; Miura, Katsuya; Kashio, Yousuke; Nishikawa, Masabumi

1991-01-01

A method was proposed previously for collection and measurement of tritiated moisture in gas stream using P 2 O 5 -desiccant. Influences of the gas humidity, the gas flow rate and the distance between gas nozzle and P 2 O 5 -desiccant layer surface on the moisture collection efficiency have been examined through experiments, and the isotope effect on the collection has been investigated. The collection efficiency is the ratio of collected to supplied moisture, and the moisture supplying rate is in proportion to the humidity and flow rate of feed gas. The experiments show that; the collection efficiency dose not depend on the gas humidity, but is affected by the gas flow rate and by the nozzle-layer distance. The effects of the flow rate and the nozzle position are related to the mass transfer distance from the bulk of gas stream to the desiccant layer surface in the collection cell. The moisture collecting rate is promoted by the approach of the gas stream to the layer surface. An expression of effective separation factor has been derived to explain the isotope effect on the moisture collection. Experimental data distribution of the separation factor have been reasonably simulated by the analysis. (author)

Dynamic moisture sorption characteristics of enzyme-resistant recrystallized cassava starch.

Science.gov (United States)

Mutungi, Christopher; Schuldt, Stefan; Onyango, Calvin; Schneider, Yvonne; Jaros, Doris; Rohm, Harald

2011-03-14

The interaction of moisture with enzyme-resistant recrystallized starch, prepared by heat-moisture treatment of debranched acid-modified or debranched non-acid-modified cassava starch, was investigated in comparison with the native granules. Crystallinities of the powdered products were estimated by X-ray diffraction. Moisture sorption was determined using dynamic vapor sorption analyzer and data fitted to various models. Percent crystallinities of native starch (NS), non-acid-modified recrystallized starch (NAMRS), and acid-modified recrystallized starch (AMRS) were 39.7, 51.9, and 56.1%, respectively. In a(w) below 0.8, sorption decreased in the order NS > NAMRS > AMRS in line with increasing sample crystallinities but did not follow this crystallinity dependence at higher a(w) because of condensation and polymer dissolution effects. Adsorbed moisture became internally absorbed in NS but not in NAMRS and AMRS, which might explain the high resistance of the recrystallized starches to digestion because enzyme and starch cannot approach each other over fairly sufficient surface at the molecular level.

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

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....

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.)

Degradation of [14C]isofenphos in soil in the laboratory under different soil pH's, temperatures, and moistures

International Nuclear Information System (INIS)

Abou-Assaf, N.; Coats, J.R.

1987-01-01

The effects of three soil pH's, three soil temperatures, and three soil moistures on [ 14 C]isofenphos degradation were investigated. All three factors interacted strongly and significantly affected the persistence of isofenphos as well as the formation of the degradation products (p less than 1%). Isofenphos degradation was greatest at the higher temperatures 35 0 C greater than 25 0 C greater than 15 0 C (except under alkaline pH's), medium moisture 25% greater than 30% greater than 15%, and in both alkaline (pH = 8) and acidic soils (pH = 6) compared with neutral soil (pH = 7). Isofenphos oxon formation was greatest at higher temperatures 35 0 C compared with 25 0 C and 15 0 C, in acidic soil greater than neutral soil greater than alkaline soil, and under high moisture (30%) compared with the 15% and 22.5% moistures. The formation of soil-bound residues was greatest at higher temperatures 35 0 C greater than 25 0 C greater than 15 0 C, higher moisture 30% compared with 15% and 22.5%, and in alkaline soil compared with neutral and acidic soils

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

Cryogenic Moisture Uptake in Foam Insulation for Space Launch Vehicles

Science.gov (United States)

Fesmire, James E.; ScholtensCoffman, Brekke E.; Sass, Jared P.; Williams, Martha K.; Smith, Trent M.; Meneghelli, Barrry J.

2008-01-01

Rigid polyurethane foams and rigid polyisocyanurate foams (spray-on foam insulation), like those flown on Shuttle, Delta IV, and will be flown on Ares-I and Ares-V, can gain an extraordinary amount of water when under cryogenic conditions for several hours. These foams, when exposed for eight hours to launch pad environments on one side and cryogenic temperature on the other, increase their weight from 35 to 80 percent depending on the duration of weathering or aging. This effect translates into several thousand pounds of additional weight for space vehicles at lift-off. A new cryogenic moisture uptake apparatus was designed to determine the amount of water/ice taken into the specimen under actual-use propellant loading conditions. This experimental study included the measurement of the amount of moisture uptake within different foam materials. Results of testing using both aged specimens and weathered specimens are presented. To better understand cryogenic foam insulation performance, cryogenic moisture testing is shown to be essential. The implications for future launch vehicle thermal protection system design and flight performance are discussed.

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.

Effective moisture diffusivity and activation energy of rambutan seed under different drying methods to promote storage stability

Science.gov (United States)

Ahmad, So'bah; Shamsul Anuar, Mohd; Saleena Taip, Farah; Shamsudin, Rosnah; M, Siti Roha A.

2017-05-01

The effects of two drying methods, oven and microwave drying on the effective moisture diffusivity and activation energy of rambutan seed were studied. Effective moisture diffusivity and activation energy are the main indicators used for moisture movement within the material. Hence, it is beneficial to determine an appropriate drying method to attain a final moisture content of rambutan seed that potentially could be used as secondary sources in the industry. An appropriate final moisture content will provide better storage stability that can extend the lifespan of the rambutan seed. The rambutan seeds were dried with two drying methods (oven and microwave) at two level of the process variables (oven temperature; 40°C and 60°C and microwave power; 250W and 1000W) at constant initial moisture contents. The result showed that a higher value of effective moisture diffusivity and less activation energy were observed in microwave drying compared to oven drying. This finding portrays microwave drying expedites the moisture removal to achieve the required final moisture content and the most appropriate drying method for longer storage stability for rambutan seed. With respect to the process variables; higher oven temperatures and lower microwave powers also exhibit similar trends. Hopefully, this study would provide a baseline data to determine an appropriate drying method for longer storage period for turning waste to by-products.

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 %.

KARAKTERISTIK FISIKO-KIMIA DAN FUNGSIONAL PATI SAGU IHUR TERMODIFIKASI DENGAN HEAT MOISTURE TREATMENT

Directory of Open Access Journals (Sweden)

Priscillia Picauly

2017-06-01

Full Text Available The objective of this study was to characterize the properties of Heat Moisture treatment (HMT modified ihur sago starch with different moisture contents. The starch was modified with HMT at 110°C after being adjusted to various moisture contents (23, 28, or 33% for 4 h. The physico-chemical and functional properties of the native and modified HMT Ihur sago starch observed were color, swelling power, solubility, paste clarity, moisture content, ash content, amylose content, phenol content, and resistant starch (RS content. Results of this study showed that the HMT starch has a higher degree of lightness (L*, redness (a*, and yellowness (b*, solubility (4.85-5.38% but lower swelling power (44.06-47.47 g/g than the native starch which has a solubility and swelling power of 4.90% and 50.72 g/g, respectively. Paste clarity was found to decrease along the storage period. In addition, higher moisture content (11.81-13.20%, but lower amylose (14.81-23.52%, phenol (2.50-4.04%, and RS (5.4-6.1% content were observed than the native starch with amylose, phenol, and RS content of 27.18, 7.91, and 6.5%, respectively.

Development of membrane moisture separator for BWR off-gas system

International Nuclear Information System (INIS)

Ogata, H.; Kawamura, S.; Kumasaka, M.; Nishikubo, M.

2001-01-01

In BWR plant off-gas treatment systems, dehumidifiers are used to maintain noble gas adsorption efficiency in the first half of the charcoal hold-up units. From the perspective of simplifying and reducing the cost of such a dehumidification system, Japanese BWR utilities and plant fabricators have been developing a dehumidification system employing moisture separation membrane of the type already proven in fields such as medical instrumentation and precision measuring apparatus. The first part of this development involved laboratory testing to simulate the conditions found in an actual off-gas system, the results of which demonstrated satisfactory results in terms of moisture separation capability and membrane durability, and suggested favorable prospects for application in actual off-gas systems. Further, in-plant testing to verify moisture separation capability and membrane durability in the presence of actual gases is currently underway, with results so far suggesting that the system is capable of obtaining good moisture separation capability. (author)

Determination of moisture in fiber reinforced composites using pulsed NMR

International Nuclear Information System (INIS)

Matzkanin, G.A.

1982-01-01

Nuclear magnetic resonance (NMR) signals from hydrogen atoms in two organic matrix composite systems subjected to environmental conditioning at 51.6 C (125 F) and 95% relative humidity were examined. The composites were 8 ply, + or - 45 deg laminates fabricated from SP 250 resin/S2 glass fiber and Reliabond 9350 resin/Kevlar 49 fiber. Free induction decay NMR signals from the composite specimens consisted of a large amplitude, fast decaying component associated with hydrogen in rigid polymer molecules and a lower amplitude, slower decaying component associated with hydrogen in the mobile absorbed moisture molecules. The absorbed moisture NMR signals consists of distinct multiple components which were attributed to moisture in various states of molecular binding. Particularly complex free induction decay signals were observed from Kevlar composite as well as from Kevlar fiber. Good correlation was obtained between the NMR signal amplitude and the dry weight moisture percentage for both composite systems. Results of destructive tensile tests were examined

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

Varying hydric conditions during incubation influence egg water exchange and hatchling phenotype in the red-eared slider turtle.

Science.gov (United States)

Delmas, Virginie; Bonnet, Xavier; Girondot, Marc; Prévot-Julliard, Anne-Caroline

2008-01-01

Environmental conditions within the nest, notably temperature and moisture of substrate, exert a powerful influence during embryogenesis in oviparous reptiles. The influence of fluctuating nest temperatures has been experimentally examined in different reptile species; however, similar experiments using moisture as the key variable are lacking. In this article, we examine the effect of various substrate moisture regimes during incubation on different traits (egg mass, incubation length, and hatchling mass) in a chelonian species with flexible-shelled eggs, the red-eared slider turtle (Trachemys scripta elegans). Our results show that the rate of water uptake by the eggs was higher in wet than in dry substrate and varied across development. More important, during the first third of development, the egg mass changes were relatively independent of the soil moisture level; they became very sensitive to moisture levels during the other two-thirds. Moreover, hydric conditions exerted a strong influence on the eggs' long-term sensitivity to the moisture of the substrate. Even short-term episodes of high or low levels of moisture modified permanently their water sensitivity, notably through modification of eggshell shape and volume, and in turn entailed significant effects on hatchling mass (and hence offspring quality). Such complex influences of fluctuating moisture levels at various incubation stages on hatchling phenotype better reflect the natural situation, compared to experiments based on stable, albeit different, moisture levels.

Specification of indoor climate design parameters at the assessment of moisture protective properties of enclosing structures

Directory of Open Access Journals (Sweden)

Kornienko Sergey Valer’evich

2016-11-01

Full Text Available Due to wide implementation of enveloping structures with increased heat-insulation properties in modern construction here appeared a necessity to assess their moisture conditions. Assessment of moisture conditions of enveloping structures is carried out according to maximum allowable moisture state basing on determining the surface of maximum damping. In relation to it the necessity of additional vapour barrier is checked using moisture balance equation. Though the change of indoor climate parameters in premises is not taken into account in moisture balance equations defined for different seasons. The author improves the method of calculating moisture protective parameters of enclosing structures according to the maximum allowable damping state for a year and a period of moisture accumulation. It is shown in this article that accounting of temperature and relative humidity change of inside air allows specifying calculated parameters of indoor climate in residential and office rooms in assessment of moisture protective properties of enclosing structures for the case of an effective enclosing structure with a façade heat-insulation composite system. Coordinates of the maximum moistened surface of the envelope depends on indoor climate design parameters. It is concluded that the increase of requirements for moisture protection of enclosing structures when using design values of temperature and relative humidity of internal air according to the Russian regulation (SP 50.13330.2012 is not always reasonable. Accounting of changes of indoor climate parameters allows more precise assessment of moisture protective properties of enclosing structures during their design.

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.

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.

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

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

product by averaging model results from the 1 km2 grid within the remote sensing footprint. Overall 440 (AMSR-E, SMOS) to 680 (ASCAT) timeseries were compared to the aggregated SWAP model results, providing valuable information on the uncertainty of satellite soil moisture at the proper support. Our results show that temporal dynamics are best captured by ASCAT resulting in an average correlation of 0.72 with the model, while ASMR-E (0.41) and SMOS (0.42) are less capable of representing these dynamics. Standard deviations found for ASCAT and SMOS are low, 0.049 and 0.051m3m-3 respectively, while AMSR-E has a higher value of 0.062m3m-3. All standard deviations are higher than the average model uncertainty of 0.017m3m-3. All satellite products show a negative bias compared to the model results, with the largest value for SMOS. Satellite uncertainty is not found to be significantly related to topography, but is found to increase in densely vegetated areas. In general AMSR-E has most difficulties capturing soil moisture dynamics in Spain, while SMOS and mainly ASCAT have a fair to good performance. However, all products contain valuable information about the near-surface soil moisture over Spain. Van Dam, J.C., 2000, Field scale water flow and solute transport. SWAP model concepts, parameter estimation and case studies. Ph.D. thesis, Wageningen University

Higher-order conditioning is impaired by hippocampal lesions.

Science.gov (United States)

Gilboa, Asaf; Sekeres, Melanie; Moscovitch, Morris; Winocur, Gordon

2014-09-22

Behavior in the real world is rarely motivated by primary conditioned stimuli that have been directly associated with potent unconditioned reinforcers. Instead, motivation and choice behavior are driven by complex chains of higher-order associations that are only indirectly linked to intrinsic reward and often exert their influence outside awareness. Second-order conditioning (SOC) [1] is a basic associative-learning mechanism whereby stimuli acquire motivational salience by proxy, in the absence of primary incentives [2, 3]. Memory-systems theories consider first-order conditioning (FOC) and SOC to be prime examples of hippocampal-independent nondeclarative memory [4, 5]. Accordingly, neurobiological models of SOC focus almost exclusively on nondeclarative neural systems that support motivational salience and reward value. Transfer of value from a conditioned stimulus to a neutral stimulus is thought to require the basolateral amygdala [6, 7] and the ventral striatum [2, 3], but not the hippocampus. We developed a new paradigm to measure appetitive SOC of tones in rats. Hippocampal lesions severely impaired both acquisition and expression of SOC despite normal FOC. Unlike controls, rats with hippocampal lesions could not discriminate between positive and negative secondary conditioned tones, although they exhibited general familiarity with previously presented tones compared with new tones. Importantly, normal rats' behavior, in contrast to that of hippocampal groups, also revealed different confidence levels as indexed by effort, a central characteristic of hippocampal relational memory. The results indicate, contrary to current systems models, that representations of intrinsic relationships between reward value, stimulus identity, and motivation require hippocampal mediation when these relationships are of a higher order. Copyright © 2014 Elsevier Ltd. All rights reserved.

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.)

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.

Feasibility analysis of using inverse modeling for estimating natural groundwater recharge from a large-scale soil moisture monitoring network

Science.gov (United States)

Wang, Tiejun; Franz, Trenton E.; Yue, Weifeng; Szilagyi, Jozsef; Zlotnik, Vitaly A.; You, Jinsheng; Chen, Xunhong; Shulski, Martha D.; Young, Aaron

2016-02-01

Despite the importance of groundwater recharge (GR), its accurate estimation still remains one of the most challenging tasks in the field of hydrology. In this study, with the help of inverse modeling, long-term (6 years) soil moisture data at 34 sites from the Automated Weather Data Network (AWDN) were used to estimate the spatial distribution of GR across Nebraska, USA, where significant spatial variability exists in soil properties and precipitation (P). To ensure the generality of this study and its potential broad applications, data from public domains and literature were used to parameterize the standard Hydrus-1D model. Although observed soil moisture differed significantly across the AWDN sites mainly due to the variations in P and soil properties, the simulations were able to capture the dynamics of observed soil moisture under different climatic and soil conditions. The inferred mean annual GR from the calibrated models varied over three orders of magnitude across the study area. To assess the uncertainties of the approach, estimates of GR and actual evapotranspiration (ETa) from the calibrated models were compared to the GR and ETa obtained from other techniques in the study area (e.g., remote sensing, tracers, and regional water balance). Comparison clearly demonstrated the feasibility of inverse modeling and large-scale (>104 km2) soil moisture monitoring networks for estimating GR. In addition, the model results were used to further examine the impacts of climate and soil on GR. The data showed that both P and soil properties had significant impacts on GR in the study area with coarser soils generating higher GR; however, different relationships between GR and P emerged at the AWDN sites, defined by local climatic and soil conditions. In general, positive correlations existed between annual GR and P for the sites with coarser-textured soils or under wetter climatic conditions. With the rapidly expanding soil moisture monitoring networks around the

The use of remotely sensed soil moisture data in large-scale models of the hydrological cycle

Science.gov (United States)

Salomonson, V. V.; Gurney, R. J.; Schmugge, T. J.

1985-01-01

Manabe (1982) has reviewed numerical simulations of the atmosphere which provided a framework within which an examination of the dynamics of the hydrological cycle could be conducted. It was found that the climate is sensitive to soil moisture variability in space and time. The challenge arises now to improve the observations of soil moisture so as to provide up-dated boundary condition inputs to large scale models including the hydrological cycle. Attention is given to details regarding the significance of understanding soil moisture variations, soil moisture estimation using remote sensing, and energy and moisture balance modeling.

Automatic pattern identification of rock moisture based on the Staff-RF model

Science.gov (United States)

Zheng, Wei; Tao, Kai; Jiang, Wei

2018-04-01

Studies on the moisture and damage state of rocks generally focus on the qualitative description and mechanical information of rocks. This method is not applicable to the real-time safety monitoring of rock mass. In this study, a musical staff computing model is used to quantify the acoustic emission signals of rocks with different moisture patterns. Then, the random forest (RF) method is adopted to form the staff-RF model for the real-time pattern identification of rock moisture. The entire process requires only the computing information of the AE signal and does not require the mechanical conditions of rocks.

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.

Soil moisture effects on seasonal temperature and precipitation forecast scores in Europe

Energy Technology Data Exchange (ETDEWEB)

Hurk, Bart van den; Camargo, Helio [Royal Netherlands Meteorological Institute, KNMI, PO Box 201, AE De Bilt (Netherlands); Doblas-Reyes, Francisco [Catalan Institute of Climate Sciences (IC3), Barcelona (Spain); European Centre for Medium-range Weather Forecasts (ECMWF), Reading (United Kingdom); Balsamo, Gianpaolo [European Centre for Medium-range Weather Forecasts (ECMWF), Reading (United Kingdom); Koster, Randal D. [NASA/Goddard Space Flight Center, Global Modeling and Assimilation Office, Greenbelt, MD (United States); Seneviratne, Sonia I. [Institute for Atmospheric and Climate Science, Zurich (Switzerland)

2012-01-15

The Second Global Land Atmosphere Coupling Experiment (GLACE2) is designed to explore the improvement of forecast skill of summertime temperature and precipitation up to 8 weeks ahead by using realistic soil moisture initialization. For the European continent, we show in this study that for temperature the skill does indeed increase up to 6 weeks, but areas with (statistically significant) lower skill also exist at longer lead times. The skill improvement is smaller than shown earlier for the US, partly because of a lower potential predictability of the European climate at seasonal time scales. Selection of extreme soil moisture conditions or a subset of models with similar initial soil moisture conditions does improve the forecast skill, and sporadic positive effects are also demonstrated for precipitation. Using realistic initial soil moisture data increases the interannual variability of temperature compared to the control simulations in the South-Central European area at longer lead times. This leads to better temperature forecasts in a remote area in Western Europe. However, the covered range of forecast dates (1986-1995) is too short to isolate a clear physical mechanism for this remote correlation. (orig.)

[Soil moisture dynamics of artificial Caragana microphylla shrubs at different topographical sites in Horqin sandy land].

Science.gov (United States)

Huang, Gang; Zhao, Xue-yong; Huang, Ying-xin; Su, Yan-gui

2009-03-01

Based on the investigation data of vegetation and soil moisture regime of Caragana microphylla shrubs widely distributed in Horqin sandy land, the spatiotemporal variations of soil moisture regime and soil water storage of artificial sand-fixing C. microphylla shrubs at different topographical sites in the sandy land were studied, and the evapotranspiration was measured by water balance method. The results showed that the soil moisture content of the shrubs was the highest in the lowland of dunes, followed by in the middle, and in the crest of the dunes, and increased with increasing depth. No water stress occurred during the growth season of the shrubs. Soil moisture content of the shrubs was highly related to precipitation event, and the relationship of soil moisture content with precipitation was higher in deep soil layer (50-180 cm) than in shallow soil layer (0-50 cm). The variation coefficient of soil moisture content was also higher in deep layer than in shallow layer. Soil water storage was increasing in the whole growth season of the shrubs, which meant that the accumulation of soil water occurred in this area. The evapotranspiriation of the shrubs occupied above 64% of the precipitation.

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.

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

Continuous data assimilation for downscaling large-footprint soil moisture retrievals

KAUST Repository

Altaf, Muhammad; Jana, Raghavendra Belur; Hoteit, Ibrahim; McCabe, Matthew

2016-01-01

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.

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.

Potential feedbacks between snow cover, soil moisture and surface energy fluxes in Southern Norway

Science.gov (United States)

Brox Nilsen, Irene; Tallaksen, Lena M.; Stordal, Frode

2017-04-01

At high latitudes, the snow season has become shorter during the past decades because snowmelt is highly sensitive to a warmer climate. Snowmelt influences the energy balance by changing the albedo and the partitioning between latent and sensible heat fluxes. It further influences the water balance by changing the runoff and soil moisture. In a previous study, we identified southern Norway as a region where significant temperature changes in summer could potentially be explained by land-atmosphere interactions. In this study we hypothesise that changes in snow cover would influence the summer surface fluxes in the succeeding weeks or months. The exceptionally warm summer of 2014 was chosen as a test bed. In Norway, evapotranspiration is not soil moisture limited, but energy limited, under normal conditions. During warm summers, however, such as in 2014, evapotranspiration can be restricted by the available soil moisture. Using the Weather Research and Forecasting (WRF) model we replace the initial ground conditions for 2014 with conditions representative of a snow-poor spring and a snow-rich spring. WRF was coupled to Noah-MP at 3 km horizontal resolution in the inner domain, and the simulations covered mid-May through September 2014. Boundary conditions used to force WRF were taken from the Era-Interim reanalysis. Snow, runoff, soil moisture and soil temperature observational data were provided by the Norwegian Water Resources and Energy Directorate for validation. The validation shows generally good agreement with observations. Preliminary results show that the reduced snowpack, hereafter "sim1" increased the air temperature by up to 5 K and the surface temperature by up to 10 K in areas affected by snow changes. The increased snowpack, hereafter "sim2", decreased the air and surface temperature by the same amount. These are weekly mean values for the first eight simulation weeks from mid May. Because of the higher net energy available ( 100 Wm-2) in sim 1, both

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.

Influence of Airflow on Laboratory Storage of High Moisture Corn Stover

Energy Technology Data Exchange (ETDEWEB)

Lynn M. Wendt; Ian J. Bonner; Amber N. Hoover; Rachel M. Emerson; William A. Smith

2014-04-01

Storing high moisture biomass for bioenergy use is a reality in many areas of the country where wet harvest conditions and environmental factors prevent dry storage from being feasible. Aerobic storage of high moisture biomass leads to microbial degradation and self-heating, but oxygen limitation can aid in material preservation. To understand the influence of oxygen presence on high moisture biomass (50 %, wet basis), three airflow rates were tested on corn stover stored in laboratory reactors. Temperature, carbon dioxide production, dry matter loss, chemical composition, fungal abundance, pH, and organic acids were used to monitor the effects of airflow on storage conditions. The results of this work indicate that oxygen availability impacts both the duration of self-heating and the severity of dry matter loss. High airflow systems experienced the greatest initial rates of loss but a shortened microbially active period that limited total dry matter loss (19 %). Intermediate airflow had improved preservation in short-term storage compared to high airflow systems but accumulated the greatest dry matter loss over time (up to 27 %) as a result of an extended microbially active period. Low airflow systems displayed the best performance with the lowest rates of loss and total loss (10 %) in storage at 50 days. Total structural sugar levels of the stored material were preserved, although glucan enrichment and xylan loss were documented in the high and intermediate flow conditions. By understanding the role of oxygen availability on biomass storage performance, the requirements for high moisture storage solutions may begin to be experimentally defined.

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.

Assessing Covariation of Holocene Monsoon Intensity and Local Moisture Conditions in Eastern and Southwestern Amazon Basin Using Speleothem δ18O and 87Sr/86Sr Values

Science.gov (United States)

Ward, B. M.; Wong, C. I.; Novello, V. F.; Silva, L.; McGee, D.; Cheng, H.; Wang, X.; Edwards, R. L.; Cruz, F. W., Sr.; Santos, R. V.

2017-12-01

δ18O records from South America offer insight into past variability of the South American Monsoon System (SAMS). Potential, however, for understanding local moisture conditions is limited as precipitation δ18O is strongly influenced by regional climate dynamics. Here we create Holocene speleothem 87Sr/86Sr records at 200-yr resolution using TIMS methods in the Center for Isotope Geochemistry at Boston College to complement existing Holocene δ18O speleothem records and investigate local moisture conditions above caves located in the eastern Amazon Basin (PAR - 4°S, 55°W) and southwestern Brazil (JAR - 21°S, 56°W). Speleothem 87Sr/86Sr variability is interpreted to reflect differences in the extent of water-rock interaction due to differences in infiltration rates under wet and dry conditions. Drier conditions promote longer residence time, enhanced water-rock interaction, and greater evolution of dripwater 87Sr/86Sr values from an initial isotopic signature acquired from the soil to the signature of the cave host rock. PAR speleothem 87Sr/86Sr values range from 0.71024 to 0.71067 and are bracketed by soil (0.71710 to 0.70956) and bedrock (0.70852 to 0.70899) values. JAR speleothem 87Sr/86Sr values range from 0.71216 to 0.71539 and are greater than bedrock values (0.70825 to 0.71219), although some speleothem values exceed the single analysis conducted of the soil isotopic composition (0.71473). JAR speleothem 87Sr/86Sr values increase from the early to mid Holocene, consistent with increase in local moisture availability associated with intensification of the SAMS suggested by decreasing δ18O values in many records from the region. Speleothem 87Sr/86Sr values at JAR decrease from the mid to late Holocene, consistent with an increase in δ18O values at PAR that suggest a decline in monsoon intensity. 87Sr/86Sr variability at JAR, however, is positively correlated with the δ18O record. Preliminary 87Sr/86Sr results from PAR are only broadly consistent with

Soil Moisture and Turgidity of Selected Robusta Coffee Clones on Alluvial Plain with Seasonal Rainfall Pattern

Directory of Open Access Journals (Sweden)

Rudy Erwiyono

2005-08-01

Full Text Available Observation on the seasonal variations of hydrological condition and turgidity of selected Robusta coffee clones has been carried out in Kaliwining Experimental Station, Indonesian Coffee and Cocoa Research Institute in Jember. The aim was to evaluate the effect of hydrological variation on the coffee plants and the degree of soil moisture effect on plant performance. Experimental site overlays on alluvial plain, + 45 m a.s.l., 8o 15’ South with D rainfall type. Observation was conducted by survey method at the experimental plots of organic fertilizer and nitogen treatments on selected Robusta coffee clones derived from rooted cuttings, i.e. BP 436, BP 42, BP 936 and BP 358. Observation was only conducted at the experimental blocks of organic matter trials of 20 l/tree/year at nitrogen (Urea application of locally recommanded rate during the subsequent years of 1999 to 2001. Parameters observed included plant turgidity and soil moisture content of three different depths, i.e. 0—20, 20—40 and 40—60 cm and the weather. Observation was carried out in five replicates designed as blocks of barn manure treatment and N-fertilizer of recommended rate as basal fertilizer. The results showed that meteorological condition and soil moisture of experimental site through the years have seasonal patterns following the seasonal pattern of rainfall. Compared to other meteorological characteristics, relative humidity dominantly determined evaporation and plant turgidity. Plant turgi-dity was not only determined by soil moisture condition, but also atmospheric demand. When relative humidity (RH was relatively high, plant turgidity was relatively stable although soil moisture of surface layers was very low, and the reversal when soil moisture content was high plant turgidity was controlled by atmospheric demand (relative humidity. With a 3—4 dry month period, relative turgidity of the coffee plants was relatively stable above 82%, except when soil

The relationship between brightness temperature and soil moisture. Selection of frequency range for microwave remote sensing

International Nuclear Information System (INIS)

Rao, K.S.; Chandra, G.; Rao, P.V.N.

1987-01-01

The analysis of brightness temperature data acquired from field and aircraft experiments demonstrates a linear relationship between soil moisture and brightness temperature. However, the analysis of brightness temperature data acquired by the Skylab radiometer demonstrates a non-linear relationship between soil moisture and brightness temperature. In view of the above and also because of recent theoretical developments for the calculation of the dielectric constant and brightness temperature under varying soil moisture profile conditions, an attempt is made to study the theoretical relationship between brightness temperature and soil moisture as a function of frequency. Through the above analysis, the appropriate microwave frequency range for soil moisture studies is recommended

Use of visible, near-infrared, and thermal infrared remote sensing to study soil moisture

Science.gov (United States)

Blanchard, M. B.; Greeley, R.; Goettelman, R.

1974-01-01

Two methods are described which are used to estimate soil moisture remotely using the 0.4- to 14.0 micron wavelength region: (1) measurement of spectral reflectance, and (2) measurement of soil temperature. The reflectance method is based on observations which show that directional reflectance decreases as soil moisture increases for a given material. The soil temperature method is based on observations which show that differences between daytime and nighttime soil temperatures decrease as moisture content increases for a given material. In some circumstances, separate reflectance or temperature measurements yield ambiguous data, in which case these two methods may be combined to obtain a valid soil moisture determination. In this combined approach, reflectance is used to estimate low moisture levels; and thermal inertia (or thermal diffusivity) is used to estimate higher levels. The reflectance method appears promising for surface estimates of soil moisture, whereas the temperature method appears promising for estimates of near-subsurface (0 to 10 cm).

Shrub encroachment alters sensitivity of soil respiration to temperature and moisture

Science.gov (United States)

Cable, Jessica M.; Barron-Gafford, Greg A.; Ogle, Kiona; Pavao-Zuckerman, Mitchell; Scott, Russell L.; Williams, David G.; Huxman, Travis E.

2012-03-01

A greater abundance of shrubs in semiarid grasslands affects the spatial patterns of soil temperature, moisture, and litter, resulting in fertile islands with potentially enhanced soil metabolic activity. The goal of this study was to quantify the microsite specificity of soil respiration in a semiarid riparian ecosystem experiencing shrub encroachment. We quantified the response of soil respiration to different microsite conditions created by big mesquite shrubs (near the trunk and the canopy edge), medium-sized mesquite, sacaton bunchgrasses, and open spaces. We hypothesized that soil respiration would be more temperature sensitive and less moisture sensitive and have a greater magnitude in shrub microsites compared with grass and open microsites. Field and incubation soil respiration data were simultaneously analyzed in a Bayesian framework to quantify the microsite-specific temperature and moisture sensitivities and magnitude of respiration. The analysis showed that shrub expansion increases the heterogeneity of respiration. Respiration has greater temperature sensitivity near the shrub canopy edge, and respiration rates are higher overall under big mesquite compared with those of the other microsites. Respiration in the microsites beneath medium-sized mesquites does not behave like a downscaled version of big mesquite microsites. The grass microsites show more similarity to big mesquite microsites than medium-sized shrubs. This study shows there can be a great deal of fine-scale spatial heterogeneity that accompanies shifts in vegetation structure. Such complexity presents a challenge in scaling soil respiration fluxes to the landscape for systems experiencing shrub encroachment, but quantifying this complexity is significantly important in determining overall ecosystem metabolic behavior.

Analysis of education conditions in higher educational institutions of Ukraine

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Олександр Петрович Бурмістенков

2016-12-01

Full Text Available The article deals with some issues related to higher technical education conditions in Ukraine, namely, training and certification of graduates of schools, training of students in higher educational institutions and motivation of students to study and teachers to improve teaching methods and deep research within the walls of institution. The causes of education level reduction are expressed. The propositions are made for improving the higher education quality

Moisture-Induced TBC Spallation on Turbine Blade Samples

Science.gov (United States)

Smialek, James

2011-01-01

Delayed failure of TBCs is a widely observed laboratory phenomenon, although many of the early observations went unreported. The weekend effect or DeskTop Spallation (DTS) is characterized by initial survival of a TBC after accelerated laboratory thermal cycling, then failure by exposure to ambient humidity or water. Once initiated, failure can occur quite dramatically in less than a second. To this end, the water drop test and digital video recordings have become useful techniques in studies at NASA (Smialek, Zhu, Cuy), DECHMA (Rudolphi, Renusch, Schuetze), and CNRS Toulouse/SNECMA (Deneux, Cadoret, Hervier, Monceau). In the present study the results for a commercial turbine blade, with a standard EB-PVD 7YSZ TBC top coat and Pt-aluminide diffusion bond coat are reported. Cut sections were intermittently oxidized at 1100, 1150, and 1200 C and monitored by weight change and visual appearance. Failures were distributed widely over a 5-100 hr time range, depending on temperature. At some opportune times, failure was captured by video recording, documenting the appearance and speed of the moisture-induced spallation process. Failure interfaces exhibited alumina scale grains, decorated with Ta-rich oxide particles, and alumina inclusions as islands and streamers. The phenomenon is thus rooted in moisture-induced delayed spallation (MIDS) of the alumina scale formed on the bond coat. In that regard, many studies show the susceptibility of alumina scales to moisture, as long as high strain energy and a partially exposed interface exist. The latter conditions result from severe cyclic oxidation conditions, which produce a highly stressed and partially damaged scale. In one model, it has been proposed that moisture reacts with aluminum in the bond coat to release hydrogen atoms that embrittle the interface. A negative synergistic effect with interfacial sulfur is also invoked.

Evaluating humidity recovery efficiency of currently available heat and moisture exchangers: a respiratory system model study

Directory of Open Access Journals (Sweden)

Jeanette Janaina Jaber Lucato

2009-06-01

Full Text Available OBJECTIVES: To evaluate and compare the efficiency of humidification in available heat and moisture exchanger models under conditions of varying tidal volume, respiratory rate, and flow rate. INTRODUCTION: Inspired gases are routinely preconditioned by heat and moisture exchangers to provide a heat and water content similar to that provided normally by the nose and upper airways. The absolute humidity of air retrieved from and returned to the ventilated patient is an important measurable outcome of the heat and moisture exchangers' humidifying performance. METHODS: Eight different heat and moisture exchangers were studied using a respiratory system analog. The system included a heated chamber (acrylic glass, maintained at 37°C, a preserved swine lung, a hygrometer, circuitry and a ventilator. Humidity and temperature levels were measured using eight distinct interposed heat and moisture exchangers given different tidal volumes, respiratory frequencies and flow-rate conditions. Recovery of absolute humidity (%RAH was calculated for each setting. RESULTS: Increasing tidal volumes led to a reduction in %RAH for all heat and moisture exchangers while no significant effect was demonstrated in the context of varying respiratory rate or inspiratory flow. CONCLUSIONS: Our data indicate that heat and moisture exchangers are more efficient when used with low tidal volume ventilation. The roles of flow and respiratory rate were of lesser importance, suggesting that their adjustment has a less significant effect on the performance of heat and moisture exchangers.

Prediction of moisture transfer parameters for convective drying of shrimp at different pretreatments

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Marcus Vinicius da COSTA

2018-04-01

Full Text Available Abstract By the analytical model proposed by Dincer and Dost, the mass transfer parameters (moisture transfer coefficient and moisture diffusivity of shrimp samples were determined. Three sets of drying experiments were performed with three samples of shrimp: without boiling (WB, boiled in salt solution (SB and boiled in salt solution and subjected to liquid smoking process (SBS. The experiments were performed under controlled conditions of drying air at temperature of 60°C and velocity of 1.5 m/s. Experimental dimensionless moisture content data were used to calculate the drying coefficients and lag factors, which were then incorporated into the analytical model for slab and cylinder shapes. The results showed an adequate fit between the experimental data and the values predicted from the correlation. The boiling is the most recommended pretreatment, because provided a shorter drying time, with high values of moisture transfer coefficient and moisture diffusivity.

Effect of moisture and freeze-thaw on mechanical properties of CRM asphalt mixture

Energy Technology Data Exchange (ETDEWEB)

Kim, Nak-Seok; Cho, Kee-Ju [Kyonggi University, Suwon(Korea)

2000-06-30

This paper presents the experimental test results on moisture and freeze-thaw resistance of hot mix crumb rubber modified (CRM) asphalt concrete mixture. To compare the differences in mechanical properties of conventional and CRM asphalt concretes, various tests were conducted under different moisture conditions and freeze-thaw cycles. Marshall mix design was also performed to determine the optimum asphalt contents for the both asphalt concrete mixtures. Test results revealed that the moisture and freeze-thaw resistance of CRM asphalt mixture was superior to the conventional asphalt concrete. As a result, it is considered that the utilization of waste tires in asphalt pavements has the potential of minimizing the damage due to the moisture and freeze-thaw. (author). 9 refs., 4 tabs., 8 figs.

Geophysical characterization of soil moisture spatial patterns in a tillage experiment

Science.gov (United States)

Martinez, G.; Vanderlinden, K.; Giráldez, J. V.; Muriel, J. L.

2009-04-01

Knowledge on the spatial soil moisture pattern can improve the characterisation of the hydrological response of either field-plots or small watersheds. Near-surface geophysical methods, such as electromagnetic induction (EMI), provide a means to map such patterns using non-invasive and non-destructive measurements of the soil apparent electrical conductivity (ECa. In this study ECa was measured using an EMI sensor and used to characterize spatially the hydrologic response of a cropped field to an intense shower. The study site is part of a long-term tillage experiment in Southern Spain in which Conventional Tillage (CT), Direct Drilling (DD) and Minimum Tillage (MT) are being evaluated since 1982. Soil ECa was measured before and after a rain event of 115 mm, near the soil surface and at deeper depth (ECas and ECad, respectively) using the EM38-DD EMI sensor. Simultaneously, elevation data were collected at each sampling point to generate a Digital Elevation Model (DEM). Soil moisture during the first survey was close to permanent wilting point and near field capacity during the second survey. For the first survey, both ECas and ECad, were higher in the CT and MT than in the DD plots. After the rain event, rill erosion appeared only in CT and MT plots were soil was uncovered, matching the drainage lines obtained from the DEM. Apparent electrical conductivity increased all over the field plot with higher increments in the DD plots. These plots showed the highest ECas and ECad values, in contrast to the spatial pattern found during the first sampling. Difference maps obtained from the two ECas and ECad samplings showed a clear difference between DD plots and CT and MT plots due to their distinct hydrologic response. Water infiltration was higher in the soil of the DD plots than in the MT and CT plots, as reflected by their ECad increment. Higher ECa increments were observed in the depressions of the terrain, where water and sediments accumulated. On the contrary, the

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.

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

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

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.

Gentle cleansing and moisturizing for patients with atopic dermatitis and sensitive skin.

Science.gov (United States)

Cheong, Wai Kwong

2009-01-01

Atopic dermatitis is a common condition characterized by pruritus, inflammation, and dryness of the skin. Inflammation disrupts the barrier function of the stratum corneum, predisposing the skin to be dry, and increases susceptibility to irritants and secondary bacterial infection. Sensitive skin is common, reported by 40-50% of women and 30% of men in the US, Europe, and Japan. Basic requirements in managing eczema and sensitive skin include effective cleansers that do not compromise skin barrier integrity, alleviation of skin dryness, and restoration of skin barrier function through the use of therapeutic moisturizers. The selection of a skin cleanser is therefore an important part of managing these conditions. Studies have reported clinical improvement with the use of soap-free cleansers in combination with topical treatments. While topical corticosteroids and immunosuppressive agents are mainstays of treatment for atopic dermatitis, therapeutic moisturizers are important adjuncts. Moisturizers improve skin hydration, reduce susceptibility to irritation, restore the integrity of the stratum corneum, and enhance the efficacy of topical corticosteroids.

Molecular Modeling for Calculation of Mechanical Properties of Epoxies with Moisture Ingress

Science.gov (United States)

Clancy, Thomas C.; Frankland, Sarah J.; Hinkley, J. A.; Gates, T. S.

2009-01-01

Atomistic models of epoxy structures were built in order to assess the effect of crosslink degree, moisture content and temperature on the calculated properties of a typical representative generic epoxy. Each atomistic model had approximately 7000 atoms and was contained within a periodic boundary condition cell with edge lengths of about 4 nm. Four atomistic models were built with a range of crosslink degree and moisture content. Each of these structures was simulated at three temperatures: 300 K, 350 K, and 400 K. Elastic constants were calculated for these structures by monitoring the stress tensor as a function of applied strain deformations to the periodic boundary conditions. The mechanical properties showed reasonably consistent behavior with respect to these parameters. The moduli decreased with decreasing crosslink degree with increasing temperature. The moduli generally decreased with increasing moisture content, although this effect was not as consistent as that seen for temperature and crosslink degree.

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 ...

Automated general temperature correction method for dielectric soil moisture sensors

Science.gov (United States)

Kapilaratne, R. G. C. Jeewantinie; Lu, Minjiao

2017-08-01

An effective temperature correction method for dielectric sensors is important to ensure the accuracy of soil water content (SWC) measurements of local to regional-scale soil moisture monitoring networks. These networks are extensively using highly temperature sensitive dielectric sensors due to their low cost, ease of use and less power consumption. Yet there is no general temperature correction method for dielectric sensors, instead sensor or site dependent correction algorithms are employed. Such methods become ineffective at soil moisture monitoring networks with different sensor setups and those that cover diverse climatic conditions and soil types. This study attempted to develop a general temperature correction method for dielectric sensors which can be commonly used regardless of the differences in sensor type, climatic conditions and soil type without rainfall data. In this work an automated general temperature correction method was developed by adopting previously developed temperature correction algorithms using time domain reflectometry (TDR) measurements to ThetaProbe ML2X, Stevens Hydra probe II and Decagon Devices EC-TM sensor measurements. The rainy day effects removal procedure from SWC data was automated by incorporating a statistical inference technique with temperature correction algorithms. The temperature correction method was evaluated using 34 stations from the International Soil Moisture Monitoring Network and another nine stations from a local soil moisture monitoring network in Mongolia. Soil moisture monitoring networks used in this study cover four major climates and six major soil types. Results indicated that the automated temperature correction algorithms developed in this study can eliminate temperature effects from dielectric sensor measurements successfully even without on-site rainfall data. Furthermore, it has been found that actual daily average of SWC has been changed due to temperature effects of dielectric sensors with a

Numerical Investigations of Moisture Distribution in a Selected Anisotropic Soil Medium

Science.gov (United States)

Iwanek, M.

2018-01-01

The moisture of soil profile changes both in time and space and depends on many factors. Changes of the quantity of water in soil can be determined on the basis of in situ measurements, but numerical methods are increasingly used for this purpose. The quality of the results obtained using pertinent software packages depends on appropriate description and parameterization of soil medium. Thus, the issue of providing for the soil anisotropy phenomenon gains a big importance. Although anisotropy can be taken into account in many numerical models, isotopic soil is often assumed in the research process. However, this assumption can be a reason for incorrect results in the simulations of water changes in soil medium. In this article, results of numerical simulations of moisture distribution in the selected soil profile were presented. The calculations were conducted assuming isotropic and anisotropic conditions. Empirical verification of the results obtained in the numerical investigations indicated statistical essential discrepancies for the both analyzed conditions. However, better fitting measured and calculated moisture values was obtained for the case of providing for anisotropy in the simulation model.

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...

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...

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.

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.

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.

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

Estimating surface soil moisture from SMAP observations using a Neural Network technique.

Science.gov (United States)

Kolassa, J; Reichle, R H; Liu, Q; Alemohammad, S H; Gentine, P; Aida, K; Asanuma, J; Bircher, S; Caldwell, T; Colliander, A; Cosh, M; Collins, C Holifield; Jackson, T J; Martínez-Fernández, J; McNairn, H; Pacheco, A; Thibeault, M; Walker, J P

2018-01-01

A Neural Network (NN) algorithm was developed to estimate global surface soil moisture for April 2015 to March 2017 with a 2-3 day repeat frequency using passive microwave observations from the Soil Moisture Active Passive (SMAP) satellite, surface soil temperatures from the NASA Goddard Earth Observing System Model version 5 (GEOS-5) land modeling system, and Moderate Resolution Imaging Spectroradiometer-based vegetation water content. The NN was trained on GEOS-5 soil moisture target data, making the NN estimates consistent with the GEOS-5 climatology, such that they may ultimately be assimilated into this model without further bias correction. Evaluated against in situ soil moisture measurements, the average unbiased root mean square error (ubRMSE), correlation and anomaly correlation of the NN retrievals were 0.037 m 3 m -3 , 0.70 and 0.66, respectively, against SMAP core validation site measurements and 0.026 m 3 m -3 , 0.58 and 0.48, respectively, against International Soil Moisture Network (ISMN) measurements. At the core validation sites, the NN retrievals have a significantly higher skill than the GEOS-5 model estimates and a slightly lower correlation skill than the SMAP Level-2 Passive (L2P) product. The feasibility of the NN method was reflected by a lower ubRMSE compared to the L2P retrievals as well as a higher skill when ancillary parameters in physically-based retrievals were uncertain. Against ISMN measurements, the skill of the two retrieval products was more comparable. A triple collocation analysis against Advanced Microwave Scanning Radiometer 2 (AMSR2) and Advanced Scatterometer (ASCAT) soil moisture retrievals showed that the NN and L2P retrieval errors have a similar spatial distribution, but the NN retrieval errors are generally lower in densely vegetated regions and transition zones.

Measuring seasonal variations of moisture in a landfill with the partitioning gas tracer test

International Nuclear Information System (INIS)

Han, Byunghyun; Jafarpour, Behnam; Gallagher, Victoria N.; Imhoff, Paul T.; Chiu, Pei C.; Fluman, Daniel A.

2006-01-01

Seven pilot-scale partitioning gas tracer tests (PGTTs) were conducted to assess the accuracy and reproducibility of this method for measuring water in municipal solid waste landfills. Tests were conducted in the same location over a 12-month period, and measured moisture conditions ranged from possible dry waste to refuse with a moisture content of 24.7%. The final moisture content of 24.7% was in reasonable agreement with gravimetric measurements of excavated refuse, where the moisture content was 26.5 ± 6.0CI%. Laboratory tests were used to assess the utility of the PGTT for measuring water in small pores, water sorbed to solid surfaces, and the influence of dry waste on PGTTs. These experiments indicated that when refuse surfaces are not completely solvated with water, PGTTs may produce misleading results (negative estimates) of water saturation and moisture content

Moisture sources of the Mono Lake deglacial pluvial events

Science.gov (United States)

Wang, X.; Liang, M. C.; Ali, G.; Shen, C. C.; Cai, Y.; Ke, L.; Hemming, S. R.

2016-12-01

Enormously expanded lakes existed in the today's dry western US Great Basin during the last glacial period. The ancient shorelines located well above modern lake levels suggest that precipitation in lake basins must have been substantially higher in the past. It is however under debate whether the subtropical North Pacific or the tropical Pacific is the major moisture source that contributed to the pluvial events, particularly during the deglaciation. Here, we collected a suite of tufa carbonate samples deposited at the 2,080 meter terrace ( 135 meters above today's lake level) in the Mono Basin, California, a closed lake basin for the last 130 thousand years (kyr). At Goat Ranch, we discovered white, shiny, laminated botryoidal carbonate coatings on tufa mounds. Most of these coatings present two generations of formation separated by a hiatus, which indicates lake level fluctuations. Using high-precision U-Th dating techniques, we found that the lower layer was formed 14.1-14.4 kyr BP (corresponding to the North Atlantic Bølling warming period). The upper layer of the coating was formed 11.9-12.3 kyr BP (within the Younger Dryas event). We then obtained d18O, d13C, D47 and 17O-excess values for the two carbonate layers. The upper part is characterized by low d18O values, -8 to -12 ‰ VPDB, whereas the lower one has higher d18O values, -5 to -6 ‰ VPDB. Both share similar d13C values ( 1-2‰ VPDB). D47 analysis on the carbonates suggests that both layers were deposited in a water temperature of 9±2 oC (1s, n = 4 and 8, respectively). The two generations of carbonates present 17O-excess of moisture in values of 50±5 (1s, n=4) and 25±5 (1s, n=8) per meg VSMOW-SLAP, respectively. The large difference in 17O-excess of parent meteoric water points to different origins of moisture for the tufa carbonate formations. The high 17O-excess values during YD suggest a moisture source with a low relative humidity, consistent with the conventional view that the moisture

Fast qualification using thermal shock combined with moisture absorption

NARCIS (Netherlands)

Ma, X.S.; Zhang, G.Q.; Jansen, K.M.B.; Driel, van W.D.; Sluis, van der O.; Ernst, L.J.; Regard, C.; Gautier, C.; Fremont, H.

2009-01-01

Time to market is becoming one of the most important factors because of the fierce market competition. However, traditional reliability and interface toughness characterization tests take very long time. For example, moisture sensitivity level assessment (MSL1) will take 168 hours pre conditioning

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...

Exploring the Role of Soil Moisture Conditions for Rainfall Triggered Landslides on Catchment Scale: the case of the Ialomita Sub Carpathians, Romania

Science.gov (United States)

Chitu, Zenaida; Bogaard, Thom; Adler, Mary-Jeanne; Steele-Dunne, Susan; Hrachowitz, Markus; Busuioc, Aristita; Sandric, Ionut; Istrate, Alexandru

2014-05-01

Like in many parts of the world, landslides represent in Romania recurrent phenomena that produce numerous damages to the infrastructure every few years. The high frequency of landslide events over the world has resulted to the development of many early warning systems that are based on the definition of rainfall thresholds triggering landslides. In Romania in particular, recent studies exploring the temporal occurrence of landslides have revealed that rainfall represents the most important triggering factor for landslides. The presence of low permeability soils and gentle slope degrees in the Ialomita Subcarpathians of Romania makes that cumulated precipitation over variable time interval and the hydraulic response of the soil plays a key role in landslides triggering. In order to identify the slope responses to rainfall events in this particular area we investigate the variability of soil moisture and its relationship to landslide events in three Subcarpathians catchments (Cricovul Dulce, Bizididel and Vulcana) by combining in situ measurements, satellite-based radiometry and hydrological modelling. For the current study, hourly soil moisture measurements from six soil moisture monitoring stations that are fitted with volumetric soil moisture sensors, temperature soil sensors and rain gauges sensors are used. Pedotransfer functions will be applied in order to infer hydraulic soil properties from soil texture sampled from 50 soil profiles. The information about spatial and temporal variability of soil moisture content will be completed with the Level 2 soil moisture products from the Soil Moisture and Ocean Salinity (SMOS) mission. A time series analysis of soil moisture is planned to be integrated to landslide and rainfall time series in order to determine a preliminary rainfall threshold triggering landslides in Ialomita Subcarpathians.

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.

Effect of sugar addition on glass transition temperatures of cassava starch with low to intermediate moisture contents.

Science.gov (United States)

Figueroa, Yetzury; Guevara, Marvilan; Pérez, Adriana; Cova, Aura; Sandoval, Aleida J; Müller, Alejandro J

2016-08-01

This work studies how sucrose (S) addition modifies the thermal properties of cassava starch (CS). Neat CS and CS-S blends with 4, 6 and 8% sugar contents (CS-S-4%, CS-S-6% and CS-S-8%) were prepared and analyzed by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA), in a wide range of moisture levels (2-20%). In equilibrated samples with moisture contents lower than 10%, twoendothermic steps were observed during first DSC heating scans and two corresponding relaxation maxima in tan δ were detected by DMTA. The first transition, detected at around 45-55°C by both DSC and DMTA, is frequently found in starchy foods, while the second observed at higher temperatures is associated to the glass transition temperature of the blends. At higher moisture contents, only one thermal transition was observed. Samples analyzed immediately after cooling from the melt (i.e., after erasing their thermal history), exhibited a single glass transition temperature, regardless of their moisture content. Addition of sugar promotes water plasticization of CS only at high moisture contents. In the low moisture content range, anti-plasticization was observed for both neat and sugar-added CS samples. Addition of sugar decreases the moisture content needed to achieve the maximum value of the glass transition temperature before plasticization starts. The results of this work may be valuable for the study of texture establishment in low moisture content extruded food products. Copyright © 2016 Elsevier Ltd. All rights reserved.

SMAP/Sentinel-1 L2 Radiometer/Radar 30-Second Scene 3 km EASE-Grid Soil Moisture V001

Data.gov (United States)

National Aeronautics and Space Administration — This Level-2 (L2) soil moisture product provides estimates of land surface conditions retrieved by both the Soil Moisture Active Passive (SMAP) radiometer during...

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

NIR-Red Spectra-Based Disaggregation of SMAP Soil Moisture to 250 m Resolution Based on SMAPEx-4/5 in Southeastern Australia

Directory of Open Access Journals (Sweden)

Nengcheng Chen

2017-01-01

Full Text Available To meet the demand of regional hydrological and agricultural applications, a new method named near infrared-red (NIR-red spectra-based disaggregation (NRSD was proposed to perform a disaggregation of Soil Moisture Active Passive (SMAP products from 36 km to 250 m resolution. The NRSD combined proposed normalized soil moisture index (NSMI with SMAP data to obtain 250 m resolution soil moisture mapping. The experiment was conducted in southeastern Australia during SMAP Experiments (SMAPEx 4/5 and validated with the in situ SMAPEx network. Results showed that NRSD performed a decent downscaling (root-mean-square error (RMSE = 0.04 m3/m3 and 0.12 m3/m3 during SMAPEx-4 and SMAPEx-5, respectively. Based on the validation, it was found that the proposed NSMI was a new alternative indicator for denoting the heterogeneity of soil moisture at sub-kilometer scales. Attributed to the excellent performance of the NSMI, NRSD has a higher overall accuracy, finer spatial representation within SMAP pixels and wider applicable scope on usability tests for land cover, vegetation density and drought condition than the disaggregation based on physical and theoretical scale change (DISPATCH has at 250 m resolution. This revealed that the NRSD method is expected to provide soil moisture mapping at 250-resolution for large-scale hydrological and agricultural studies.

A flash flood early warning system based on rainfall thresholds and daily soil moisture indexes

Science.gov (United States)

Brigandì, Giuseppina; Tito Aronica, Giuseppe

2015-04-01

Main focus of the paper is to present a flash flood early warning system, developed for Civil Protection Agency for the Sicily Region, for alerting extreme hydrometeorological events by using a methodology based on the combined use of rainfall thresholds and soil moisture indexes. As matter of fact, flash flood warning is a key element to improve the Civil Protection achievements to mitigate damages and safeguard the security of people. It is a rather complicated task, particularly in those catchments with flashy response where even brief anticipations are important and welcomed. In this context, some kind of hydrological precursors can be considered to improve the effectiveness of the emergency actions (i.e. early flood warning). Now, it is well known how soil moisture is an important factor in flood formation, because the runoff generation is strongly influenced by the antecedent soil moisture conditions of the catchment. The basic idea of the work here presented is to use soil moisture indexes derived in a continuous form to define a first alert phase in a flash flood forecasting chain and then define a unique rainfall threshold for a given day for the subsequent alarm phases activation, derived as a function of the soil moisture conditions at the beginning of the day. Daily soil moisture indexes, representative of the moisture condition of the catchment, were derived by using a parsimonious and simply to use approach based on the IHACRES model application in a modified form developed by the authors. It is a simple, spatially-lumped rainfall-streamflow model, based on the SCS-CN method and on the unit hydrograph approach that requires only rainfall, streamflow and air temperature data. It consists of two modules. In the first a non linear loss model, based on the SCS-CN method, was used to transform total rainfall into effective rainfall. In the second, a linear convolution of effective rainfall was performed using a total unit hydrograph with a configuration of

Effect of land-use practice on soil moisture variability for soils covered with dense forest vegetation of Puerto Rico

Science.gov (United States)

Tsegaye, T.; Coleman, T.; Senwo, Z.; Shaffer, D.; Zou, X.

1998-01-01

Little is known about the landuse management effect on soil moisture and soil pH distribution on a landscape covered with dense tropical forest vegetation. This study was conducted at three locations where the history of the landuse management is different. Soil moisture was measured using a 6-cm three-rod Time Domain Reflectometery (TDR) probe. Disturbed soil samples were taken from the top 5-cm at the up, mid, and foothill landscape position from the same spots where soil moisture was measured. The results showed that soil moisture varies with landscape position and depth at all three locations. Soil pH and moisture variability were found to be affected by the change in landuse management and landscape position. Soil moisture distribution usually expected to be relatively higher in the foothill (P3) area of these forests than the uphill (P1) position. However, our results indicated that in the Luquillo and Guanica site the surface soil moisture was significantly higher for P1 than P3 position. These suggest that the surface and subsurface drainage in these two sites may have been poor due to the nature of soil formation and type.

A novel shredder for municipal solid waste (MSW): influence of feed moisture on breakage performance.

Science.gov (United States)

Luo, Siyi; Xiao, Bo; Xiao, Lei

2010-08-01

A novel MSW shredder was presented but many aspects of the shredder have not been fully characterized. The feed moisture is an important factor that influences crushing performance. This paper focuses on the effect of feed moisture. The breakage of municipal solid waste (MSW) at several moisture levels (0%, 10%, 20%, 40% and 60%) was conducted with a laboratory shredder to investigate the effect of feed moisture on product size distribution and specific energy consumption under two different hydraulic pressures (40 and 60 kg/cm(2)). The results showed definite effects of feed moisture on the product size distribution and specific energy consumption: there is a tendency for the fine production in products to decrease with increasing amounts of water content in the feed; with the increasing feed moisture, specific energy shows an increasing trend; the specific energy and product size distribution under lower hydraulic pressure is more sensitive to the feed moisture than it is under higher hydraulic pressure. (c) 2010. Published by Elsevier Ltd. All rights reserved.

Mapping the Holocene forest formations with the use of key climate indicators – heat and moisture

Directory of Open Access Journals (Sweden)

S. K. Farber

2017-12-01

Full Text Available The article deals with the methodology of mapping the Holocene forest formations on the basis of the DEM and the key indicators of the climate – heat and moisture. The work is carried out by means of GIS. The test site is located within the boundaries of the axial West Sayan district of mountain taiga forests, which ensures homogeneity of natural and climatic conditions. Stages of the method: creation of rasters on groups of absolute heights, exposures and inclinations with their subsequent combination into a single Combine raster; obtaining the regularities of spatial distribution of heat and moisture and their representation in the form of rasters (digital models; and interactive mapping of the Holocene forests with various combinations of heat and moisture. The use of Combine raster makes it possible to refuse to use any other contours as – landscape, geomorphological, forest inventory. To determine parameters of climatic boundaries of forest formations, the types of forests are linked to the heat and moisture indicators. As a result of linking, a graphic image is produced, where forest formations and their productivity are located in a certain order. The mapping technique involves creating a dBASE table with a field containing information about forest formations. The row-wise change in the records of forest formations as they move to other values of heat and moisture is performed interactively. Each next combination of heat and moisture on maps corresponds to a certain distribution of forest formations and site productivity (bonitet classes. (1900 ± 65 years ago the river valleys were treeless, flat meadows occupied meadows, and the slopes were steppes. As the hypsometric level increases, larch stands, spruce-Siberian stone pine with an admixture of larch, Siberian stone pine-larch with an admixture of fir, and the Siberian stone pine formations appear. (2200 ± 100 years ago the tundra prevailed. Larch forests of V–Va classes of

Spatial downscaling of SMAP soil moisture using MODIS land surface temperature and NDVI during SMAPVEX15

Science.gov (United States)

The SMAP (Soil Moisture Active Passive) mission provides global surface soil moisture product at 36 km resolution from its L-band radiometer. While the coarse resolution is satisfactory to many applications there are also a lot of applications which would benefit from a higher resolution soil moistu...

An experimental set-up to test heat-moisture exchangers

NARCIS (Netherlands)

Unal, N.; Pompe, J. C.; Holland, W. P.; Gültuna, I.; Huygen, P. E.; Jabaaij, K.; Ince, C.; Saygin, B.; Bruining, H. A.

1995-01-01

The purpose of this study was to build an experimental set-up to assess continuously the humidification, heating and resistance properties of heat-moisture exchangers (HMEs) under clinical conditions. The experimental set-up consists of a patient model, measurement systems and a ventilator. Surgical

Effects of moisture on glass fiber-reinforced polymer composites

DEFF Research Database (Denmark)

Alzamora Guzman, Vladimir Joel; Brøndsted, Povl

2015-01-01

performance of wind turbine blades over their lifetime. Here, environmental moisture conditions were simulated by immersing glass fiber-reinforced polymer specimens in salt water for a period of up to 8 years. The mechanical properties of specimens were analyzed before and after immersion to evaluate...

On moisture migration in a heated concrete

International Nuclear Information System (INIS)

Shiina, Yasuaki

1985-10-01

Transient moisture migration in a slab of porous concrete being heated at one surface was analyzed with consideration of evaporation and condensation effects. Analysis was made in the existence of non-condensable fluid (air). Since partial differential equations which describe the total system are very complicated, the existence of similar solution is assumed under the condition of low dry-wet interface temperature. Then, partial differential equations were transformed into ordinary differential equations. Solutions were obtained for two boundary conditions of a permeable outer surface and a impermeable outer surface. (author)

Effect of temperature and moisture on the mineralization and humification of leaf litter in a model incubation experiment

Science.gov (United States)

Larionova, A. A.; Maltseva, A. N.; Lopes de Gerenyu, V. O.; Kvitkina, A. K.; Bykhovets, S. S.; Zolotareva, B. N.; Kudeyarov, V. N.

2017-04-01

The mineralization and humification of leaf litter collected in a mixed forest of the Prioksko-Terrasny Reserve depending on temperature (2, 12, and 22°C) and moisture (15, 30, 70, 100, and 150% of water holding capacity ( WHC)) has been studied in long-term incubation experiments. Mineralization is the most sensitive to temperature changes at the early stage of decomposition; the Q 10 value at the beginning of the experiment (1.5-2.7) is higher than at the later decomposition stages (0.3-1.3). Carbon losses usually exceed nitrogen losses during decomposition. Intensive nitrogen losses are observed only at the high temperature and moisture of litter (22°C and 100% WHC). Humification determined from the accumulation of humic substances in the end of incubation decreases from 34 to 9% with increasing moisture and temperature. The degree of humification CHA/CFA is maximum (1.14) at 12°C and 15% WHC; therefore, these temperature and moisture conditions are considered optimal for humification. Humification calculated from the limit value of litter mineralization is almost independent of temperature, but it significantly decreases from 70 to 3% with increasing moisture. A possible reason for the difference between the humification values measured by two methods is the conservation of a significant part of hemicelluloses, cellulose, and lignin during the transformation of litter and the formation of a complex of humic substances with plant residues, where HSs fulfill a protectoral role and decrease the decomposition rate of plant biopolymers.

Efficient low-power wireless communication setup for an autonomous soil moisture sensor

Science.gov (United States)

Surducan, Vasile; Surducan, Emanoil

2017-12-01

During July 2016 - September 2017, a micro-irrigation system was set up and tested in field and greenhouse-like conditions, using eight inexpensive soil moisture sensors designed and manufactured in our institute. Each sensor was powered by accumulators charged by an (8 × 14) cm2 solar panel. The energy budget was carefully managed to allow long operating time for both the moisture sensor and the irrigation automation. We present here the hardware-software setup implemented in our proprietary moisture sensor for wireless communication, using Bluetooth Low Energy modules (BLE). The autonomy of the system may reach 4-5 cloudy days without the need of recharging the accumulators from the sun. Over the entire operating period, the moisture sensors send data wirelessly every sampling time (15 to 30 minutes) following water drips on the soil for the next 30 seconds, pushed by a low power micro pump. The micro-irrigation process is repeated every sampling time, until the soil moisture threshold is reached. In between the operating states, the sensor and watering automation go to sleep. The software algorithm ensures low energy (max. 2.8 mWh) consumption for the moisture sensor and 20 mWh for the irrigation automation, substantially increasing the accumulators discharge cycle.

The Effect of Altered Soil Moisture on Hybridization Rate in a Crop-Wild System (Raphanus spp..

Directory of Open Access Journals (Sweden)

Lesley G Campbell

Full Text Available Since plant mating choices are flexible and responsive to the environment, rates of spontaneous hybridization may vary across ecological clines. Developing a robust and predictive framework for rates of plant gene flow requires assessing the role of environmental sensitivity on plant reproductive traits, relative abundance, and pollen vectors. Therefore, across a soil moisture gradient, we quantified pollinator movement, life-history trait variation, and unidirectional hybridization rates from crop (Raphanus sativus to wild (Raphanus raphanistrum radish populations. Both radish species were grown together in relatively dry (no rain, relatively wet (double rain, or control soil moisture conditions in Ohio, USA. We measured wild and crop radish life-history, phenology and pollinator visitation patterns. To quantify hybridization rates from crop-to-wild species, we used a simply inherited morphological marker to detect F1 hybrid progeny. Although crop-to-wild hybridization did not respond to watering treatments, the abundance of hybrid offspring was higher in fruits produced late in the period of phenological overlap, when both species had roughly equal numbers of open flowers. Therefore, the timing of fruit production and its relationship to flowering overlap may be more important to hybrid zone formation in Raphanus spp. than soil moisture or pollen vector movements.

Indoor climate and moisture durability performances of houses with unvented attic roof constructions in a mixed-humid climate.

Energy Technology Data Exchange (ETDEWEB)

Pallin, Simon B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Boudreaux, Philip R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jackson, Roderick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-10-01

A sealed or unvented attic is an energy-efficient envelope component that can reduce the amount of energy a house consumes for space conditioning if the air handler and/or ducts are located in the attic. The attic is typically sealed by using spray foam on the underside of the roof deck and covering the soffit, ridge and gable vents to minimize air leakage from the attic to the outside. This approach can save up to 10% in space-conditioning energy when ducts are located in the attic (DOE 2013). Past research done by ORNL and Florida Solar Energy Center suggests that in more hot, humid climates, an unvented attic could potentially create a more humid, uncomfortable living environment than a vented attic (Colon 2011, Boudreaux, Pallin et al. 2013). Research showed that controlling the higher indoor humidity could reduce the energy savings from the sealed, unvented attic, which in turn would decrease the energy savings payback. Research also showed that the roof assembly (5.5 inches of open-cell foam, 1inch of closed-cell foam, OSB, felt paper, and asphalt shingles) stored moisture, thus acting as a moisture buffer. During the fall and winter, the roof assembly stored moisture and during the spring and summer it released moisture. This phenomenon is not seen in a vented attic, in which the air exchange rate to the outside is greater and, in the winter, helps to dehumidify the attic air. It was also seen that in a vented attic, the direction of water vapor diffusion is on average from the attic to the interior of the house. Air leakage from the attic to the interior also occurs during more of the year in a house with an unvented attic than in one with a vented attic. These discoveries show that the moisture dynamics in a house with an unvented attic are much different from those in a house with a vented attic. This study reports on a series of computer model investigations completed to determine the key variables impacting indoor comfort and the durability of roof

Determination of effective moisture diffusivity and drying kinetics for poplar sawdust by thermogravimetric analysis under isothermal condition.

Science.gov (United States)

Chen, Dengyu; Zheng, Yan; Zhu, Xifeng

2012-03-01

The current study presents a thermogravimetric method to determine the effective moisture diffusivity and drying kinetics of biomass. Drying experiments on poplar sawdust were performed at four temperatures (60, 70, 80, and 90°C) by a thermogravimetric analyzer (TGA). The major assumption in experimentally determining effective diffusivity by Fick's diffusion equation is that drying is mass transfer limited and temperature remains isothermal during drying. The results indicated that TGA could well achieve these determining conditions. The drying process of sawdust mostly took place in the falling rate period. Midilli-Kucuk model showed the best fit for all experimental data. The effective diffusivity values changed from 9.38 × 10(-10)m(2)/s to 1.38 × 10(-9)m(2)/s within the given temperature range, and the activation energy was calculated to be 12.3 kJ/mol. Copyright © 2011 Elsevier Ltd. All rights reserved.

Extrapolating effects of conservation tillage on yield, soil moisture and dry spell mitigation using simulation modelling

Science.gov (United States)

Mkoga, Z. J.; Tumbo, S. D.; Kihupi, N.; Semoka, J.

There is big effort to disseminate conservation tillage practices in Tanzania. Despite wide spread field demonstrations there has been some field experiments meant to assess and verify suitability of the tillage options in local areas. Much of the experiments are short lived and thus long term effects of the tillage options are unknown. Experiments to study long term effects of the tillage options are lacking because they are expensive and cannot be easily managed. Crop simulation models have the ability to use long term weather data and the local soil parameters to assess long term effects of the tillage practices. The Agricultural Production Systems Simulator (APSIM) crop simulation model; was used to simulate long term production series of soil moisture and grain yield based on the soil and weather conditions in Mkoji sub-catchment of the great Ruaha river basin in Tanzania. A 24 year simulated maize yield series based on conventional tillage with ox-plough, without surface crop residues (CT) treatment was compared with similar yield series based on conservation tillage (ox-ripping, with surface crop residues (RR)). Results showed that predicted yield averages were significantly higher in conservation tillage than in conventional tillage ( P APSIM simulation model, showed that average soil moisture in the conservation tillage was significantly higher ( P < 0.05) (about 0.29 mm/mm) than in conventional tillage (0.22 mm/mm) treatment during the seasons which received rainfall between 468 and 770 mm. Similarly the conservation tillage treatment recorded significantly higher yields (4.4 t/ha) ( P < 0.01) than the conventional tillage (3.6 t/ha) treatment in the same range of seasonal rainfall. On the other hand there was no significant difference in soil moisture for the seasons which received rainfall above 770 mm. In these seasons grain yield in conservation tillage treatment was significantly lower (3.1 kg/ha) than in the conventional tillage treatment (4.8 kg

What determines transitions between energy- and moisture-limited evaporative regimes?

Science.gov (United States)

Haghighi, E.; Gianotti, D.; Akbar, R.; Salvucci, G.; Entekhabi, D.

2017-12-01

The relationship between evaporative fraction (EF) and soil moisture (SM) has traditionally been used in atmospheric and land-surface modeling communities to determine the strength of land-atmosphere coupling in the context of the dominant evaporative regime (energy- or moisture-limited). However, recent field observations reveal that EF-SM relationship is not unique and could vary substantially with surface and/or meteorological conditions. This implies that conventional EF-SM relationships (exclusive of surface and meteorological conditions) are embedded in more complex dependencies and that in fact it is a multi-dimensional function. To fill the fundamental knowledge gaps on the important role of varying surface and meteorological conditions not accounted for by the traditional evaporative regime conceptualization, we propose a generalized EF framework using a mechanistic pore-scale model for evaporation and energy partitioning over drying soil surfaces. Nonlinear interactions among the components of the surface energy balance are reflected in a critical SM that marks the onset of transition between energy- and moisture-limited evaporative regimes. The new generalized EF framework enables physically based estimates of the critical SM, and provides new insights into the origin of land surface EF partitioning linked to meteorological input data and the evolution of land surface temperature during surface drying that affect the relative efficiency of surface energy balance components. Our results offer new opportunities to advance predictive capabilities quantifying land-atmosphere coupling for a wide range of present and projected meteorological input data.

Effects of atmospheric moisture on rock resistivity.

Science.gov (United States)

Alvarez, R.

1973-01-01

This study examines the changes in resistivity of rock samples as induced by atmospheric moisture. Experiments were performed on samples of hematitic sandstone, pyrite, and galena. The sandstone underwent a change in resistivity of four orders of magnitude when it was measured in a vacuum of 500 ntorr and in air of 37% relative humidity. Pyrite and galena showed no variations in resistivity when they were measured under the same conditions. These results, plus others obtained elsewhere, indicate that rocks of the resistive type are affected in their electrical properties by atmospheric moisture, whereas rocks of the conductive type are not. The experimental evidence obtained is difficult to reconcile with a model of aqueous electrolytic conduction on the sample surface. It is instead suggested that adsorbed water molecules alter the surface resistivity in a manner similar to that observed in semiconductors and insulators.

Retrieving soil moisture for non-forested areas using PALS radiometer measurements in SMAPVEX12 field campaign

Science.gov (United States)

In this paper we investigate retrieval of soil moisture based on L-band brightness temperature under diverse conditions and land cover types. We apply the PALS (Passive Active L-band System) radiometer data collected in the SMAPVEX12 (Soil Moisture Active Passive Validation Experiment 2012) field ex...

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.

THE INFLUENCE OF RAW MATERIAL ON THE LIQUID MOISTURE TRANSPORT THROUGH KNITTED FABRIC

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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.

Assimilating satellite soil moisture into rainfall-runoff modelling: towards a systematic study

Science.gov (United States)

Massari, Christian; Tarpanelli, Angelica; Brocca, Luca; Moramarco, Tommaso

2015-04-01

Soil moisture is the main factor for the repartition of the mass and energy fluxes between the land surface and the atmosphere thus playing a fundamental role in the hydrological cycle. Indeed, soil moisture represents the initial condition of rainfall-runoff modelling that determines the flood response of a catchment. Different initial soil moisture conditions can discriminate between catastrophic and minor effects of a given rainfall event. Therefore, improving the estimation of initial soil moisture conditions will reduce uncertainties in early warning flood forecasting models addressing the mitigation of flood hazard. In recent years, satellite soil moisture products have become available with fine spatial-temporal resolution and a good accuracy. Therefore, a number of studies have been published in which the impact of the assimilation of satellite soil moisture data into rainfall-runoff modelling is investigated. Unfortunately, data assimilation involves a series of assumptions and choices that significantly affect the final result. Given a satellite soil moisture observation, a rainfall-runoff model and a data assimilation technique, an improvement or a deterioration of discharge predictions can be obtained depending on the choices made in the data assimilation procedure. Consequently, large discrepancies have been obtained in the studies published so far likely due to the differences in the implementation of the data assimilation technique. On this basis, a comprehensive and robust procedure for the assimilation of satellite soil moisture data into rainfall-runoff modelling is developed here and applied to six subcatchment of the Upper Tiber River Basin for which high-quality hydrometeorological hourly observations are available in the period 1989-2013. The satellite soil moisture product used in this study is obtained from the Advanced SCATterometer (ASCAT) onboard Metop-A satellite and it is available since 2007. The MISDc ("Modello Idrologico Semi

Estimation of improved resolution soil moisture in vegetated areas using passive AMSR-E data

Science.gov (United States)

Moradizadeh, Mina; Saradjian, Mohammad R.

2018-03-01

Microwave remote sensing provides a unique capability for soil parameter retrievals. Therefore, various soil parameters estimation models have been developed using brightness temperature (BT) measured by passive microwave sensors. Due to the low resolution of satellite microwave radiometer data, the main goal of this study is to develop a downscaling approach to improve the spatial resolution of soil moisture estimates with the use of higher resolution visible/infrared sensor data. Accordingly, after the soil parameters have been obtained using Simultaneous Land Parameters Retrieval Model algorithm, the downscaling method has been applied to the soil moisture estimations that have been validated against in situ soil moisture data. Advance Microwave Scanning Radiometer-EOS BT data in Soil Moisture Experiment 2003 region in the south and north of Oklahoma have been used to this end. Results illustrated that the soil moisture variability is effectively captured at 5 km spatial scales without a significant degradation of the accuracy.

Monitoring the Vadose Zone Moisture Regime Below a Surface Barrier

Science.gov (United States)

Zhang, Z. F.; Strickland, C. E.; Field, J. G.

2009-12-01

A 6000 m2 interim surface barrier has been constructed over a portion of the T Tank Farm in the Depart of Energy’s Hanford site. The purpose of using a surface barrier was to reduce or eliminate the infiltration of meteoric precipitation into the contaminated soil zone due to past leaks from Tank T-106 and hence to reduce the rate of movement of the plume. As part of the demonstration effort, vadose zone moisture is being monitored to assess the effectiveness of the barrier on the reduction of soil moisture flow. A vadose zone monitoring system was installed to measure soil water conditions at four horizontal locations (i.e., instrument Nests A, B, C, and D) outside, near the edge of, and beneath the barrier. Each instrument nest consists of a capacitance probe with multiple sensors, multiple heat-dissipation units, and a neutron probe access tube used to measure soil-water content and soil-water pressure. Nest A serves as a control by providing subsurface conditions outside the influence of the surface barrier. Nest B provides subsurface measurements to assess barrier edge effects. Nests C and D are used to assess the impact of the surface barrier on soil-moisture conditions beneath it. Monitoring began in September 2006 and continues to the present. To date, the monitoring system has provided high-quality data. Results show that the soil beneath the barrier has been draining from the shallower depth. The lack of climate-caused seasonal variation of soil water condition beneath the barrier indicates that the surface barrier has minimized water exchange between the soil and the atmosphere.

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%.

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

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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%.

Theoretical study of soil water balance and process of soil moisture evaporation

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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.

Sensitivity Analysis of b-factor in Microwave Emission Model for Soil Moisture Retrieval: A Case Study for SMAP Mission

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Dugwon Seo

2010-05-01

Full Text Available Sensitivity analysis is critically needed to better understand the microwave emission model for soil moisture retrieval using passive microwave remote sensing data. The vegetation b-factor along with vegetation water content and surface characteristics has significant impact in model prediction. This study evaluates the sensitivity of the b-factor, which is function of vegetation type. The analysis is carried out using Passive and Active L and S-band airborne sensor (PALS and measured field soil moisture from Southern Great Plains experiment (SGP99. The results show that the relative sensitivity of the b-factor is 86% in wet soil condition and 88% in high vegetated condition compared to the sensitivity of the soil moisture. Apparently, the b-factor is found to be more sensitive than the vegetation water content, surface roughness and surface temperature; therefore, the effect of the b-factor is fairly large to the microwave emission in certain conditions. Understanding the dependence of the b-factor on the soil and vegetation is important in studying the soil moisture retrieval algorithm, which can lead to potential improvements in model development for the Soil Moisture Active-Passive (SMAP mission.

A comparison of the moisture gauge and the neutron log in air-filled holes at NTS

International Nuclear Information System (INIS)

Hearst, J.R.; Carlson, R.C.

1993-08-01

Two methods are commonly used to measure water content of geologic materials by neutron diffusion, the moisture gauge and the neutron log. Both are used at NTS, the moisture gauge in tunnels, the neutron log in vertical drilled holes. In this work, the moisture gauge and the neutron log are compared for use in air-filled holes NTS. The measurement instruments have evolved with very different operational characteristics and one important physics difference, the source to detector spacing. The moisture gauge has a very short, 0--6 cm spacing, with little internal shielding, and count increases with water. The neutron log has a long spacing, 30--50 cm, substantial internal shielding, and exhibits decreasing count with increasing water. The moisture gauge gives better bed resolution than the neutron log. Because its count increases with water, the moisture gauge is more strongly affected by water in the borehole, especially in dry formations. In these conditions the neutron log is the method of choice. In air-filled holes, if source size or logging time is not a constraint, the relative sensitivity of the two tools to water is determined by the relative strengths of borehole effects as fluid, holesize, or tool-wall gap. If source size is a constraint for safety reasons, the short spacing provides higher countrates for a given detector efficiency and thus better relative precision in determining the true count. If source size is limited because of detector or electronics saturation, the short spacing will be better at high water content, while the long spacing will be better at low water content. The short spacing may have an advantage because it can make better contact with the hole wall and can be more easily corrected for gap. The long spacing tool is currently used in vertical holes at NTS because that is the only tool available from logging contractors. Since they are most concerned with high water contents, the short spacing tool could prove to be better

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.

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

Mechanisms of survival, responses and sources of Salmonella in low-moisture environments

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Sarah eFinn

2013-11-01

Full Text Available Some Enterobacteriaceae possess the ability to survive in low-moisture environments for extended periods of time. Many of the reported food-borne outbreaks associated with low-moisture foods involve Salmonella contamination. The control of Salmonella in low-moisture foods and their production environments represents a significant challenge for all food manufacturers. This review summarises the current state of knowledge with respect to Salmonella survival in intermediate- and low-moisture food matrices and their production environments. The mechanisms utilised by this bacterium to ensure their survival in these dry conditions remain to be fully elucidated, however in depth transcriptiomic data is now beginning to emerge regarding this observation. Earlier research work described the effect(s that low-moisture can exert on the long-term persistence and heat tolerance of Salmonella, however, data are also now available highlighting the potential cross-tolerance to other stressors including commonly used microbicidal agents. Sources and potential control measures to reduce the risk of contamination will be explored. By extending our understanding of these geno- and phenotypes, we may be able to exploit them to improve food safety and protect public health.

Does Greenland need a guideline on how to deal with moisture in the construction phase?

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place

2012-01-01

. As the requirements concerning moisture control are function-based, the construction client and the authorities are entrusted with interpreting requirements in a specific case, which caused the introduction of a guideline based on humidity risk classes. This paper presents the Danish requirements and guideline...... and gives examples of moisture-related problems in buildings in Greenland. Requirements and guidelines are needed in Greenland in order to deal with moisture in the construction phase, but as the conditions for constructing houses and the way that houses are used in Greenland are different from Denmark...

Moisture Adsorption Isotherm and Storability of Hazelnut Inshells and Kernels Produced in Oregon, USA.

Science.gov (United States)

Jung, Jooyeoun; Wang, Wenjie; McGorrin, Robert J; Zhao, Yanyun

2018-02-01

Moisture adsorption isotherms and storability of dried hazelnut inshells and kernels produced in Oregon were evaluated and compared among cultivars, including Barcelona, Yamhill, and Jefferson. Experimental moisture adsorption data fitted to Guggenheim-Anderson-de Boer (GAB) model, showing less hygroscopic properties in Yamhill than other cultivars of inshells and kernels due to lower content of carbohydrate and protein, but higher content of fat. The safe levels of moisture content (MC, dry basis) of dried inshells and kernels for reaching kernel water activity (a w ) ≤0.65 were estimated using the GAB model as 11.3% and 5.0% for Barcelona, 9.4% and 4.2% for Yamhill, and 10.7% and 4.9% for Jefferson, respectively. Storage conditions (2 °C at 85% to 95% relative humidity [RH], 10 °C at 65% to 75% RH, and 27 °C at 35% to 45% RH), times (0, 4, 8, or 12 mo), and packaging methods (atmosphere vs. vacuum) affected MC, a w , bioactive compounds, lipid oxidation, and enzyme activity of dried hazelnut inshells or kernels. For inshells packaged at woven polypropylene bag, MC and a w of inshells and kernels (inside shells) increased at 2 and 10 °C, but decreased at 27 °C during storage. For kernels, lipid oxidation and polyphenol oxidase activity also increased with extended storage time (P adsorption and physicochemical and enzymatic stability during storage. Moisture adsorption isotherm of hazelnut inshells and kernels is useful for predicting the storability of nuts. This study found that water adsorption and storability varied among the different cultivars of nuts, in which Yamhill was less hygroscopic than Barcelona and Jefferson, thus more stable during storage. For ensuring food safety and quality of nuts during storage, each cultivar of kernels should be dried to a certain level of MC. Lipid oxidation and enzyme activity of kernel could be increased with extended storage time. Vacuum packaging was recommended to kernels for reducing moisture adsorption

Compact RFID Enabled Moisture Sensor

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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.

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

Modeling temperature and moisture fields in conditioned spaces using zonal approach, including sorption phenomena in buildings materials; Modelisation thermo-hydro-aeraulique des locaux climatises selon l'approche zonale (prise en compte des phenomenes de sorption d'humidite)

Energy Technology Data Exchange (ETDEWEB)

Cordeiro Mendoca, K.

2004-05-15

Building simulation models represent in our days an important tool for building conception and performance analysis. Although moisture interacts in many ways with the whole building affecting therefore its behavior, frequently these models neglects the interactions between them. In addition, in most of them, indoor air conditions are considered uniform, which is a non-realistic assumption in conditioned spaces. In this work, a model to predict temperature and moisture fields in conditioned spaces, using zonal approach, is proposed. This method is based in dividing spatially a room in a relative small number of zones, typically on the order of tens to hundreds, where the state variables of air are considered uniform, with the exception of pressure that varies hydrostatically. While not as fine-grained as CFD simulation, zonal models do give useful information about temperature and moisture distributions that is important in comfort analysis. The proposed model was structured in three groups of sub-models representing the three building domains: indoor air, envelope and HVAC system. The indoor air sub-model is related to the indoor air space, where airflow speed can be considered weak. The envelope sub-model is related to the radiation exchanges between envelope and its neighborhood, and to the simultaneous heat and mass transfers across the envelope material. This latest can be represented by four sub-models of different complexity levels, with two of them taking into account moisture adsorption and desorption by building materials. Concerning to the HVAC system model, it refers to the whole system that means equipment, control and specific airflow from equipment. All sub-models were coupled into a modular simulation environment, SPARK, well-adapted to compare different models. The applicability of the proposed model is shown by two examples. The first one shows the importance of considering moisture sorption phenomena in the prediction of indoor air conditions

ENZYMATIC HYDROLYSIS LIGNIN DERIVED FROM CORN STOVER AS AN INTRINSTIC BINDER FOR BIO-COMPOSITES MANUFACTURE: EFFECT OF FIBER MOISTURE CONTENT AND PRESSING TEMPERATURE ON BOARDS’ PROPERTIES

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Guanben Du

2011-02-01

Full Text Available Binderless fiberboards from enzymatic hydrolysis lignin (EHL and cotton stalk fibers were prepared under various manufacturing conditions, and their physico-mechanical properties were evaluated. Full factorial experimental design was used to assess the effect of fiber moisture content and pressing temperature on boards’ properties. In addition, differential scanning calorimetry (DSC was used to obtain the glass transition temperature (Tg of EHL. We found that both fiber moisture content and pressing temperature had significant effects on binderless fiberboards’ properties. High fiber moisture content and pressing temperature are suggested to contribute to the self-bonding improvement among fibers with lignin-rich surface mainly by thermal softening enzymatic hydrolysis lignin. In this experiment, the optimized pressing temperature applied in binderless fiberboard production should be as high as 190°C in accordance with the EHL Tg value of 189.4°C, and the fiber moisture content should be limited to less than 20% with a higher board density of 950 kg/m3 to avoid the delamination of boards during hot pressing.

Microwave remote sensing of soil moisture for estimation of profile soil property

International Nuclear Information System (INIS)

Mattikalli, N.M.; Engman, E.T.; Ahuja, L.R.; Jackson, T.J.

1998-01-01

Multi-temporal microwave remotely-sensed soil moisture has been utilized for the estimation of profile soil property, viz. the soil hydraulic conductivity. Passive microwave remote sensing was employed to collect daily soil moisture data across the Little Washita watershed, Oklahoma, during 10-18 June 1992. The ESTAR (Electronically Steered Thin Array Radiometer) instrument operating at L -band was flown on a NASA C-130 aircraft. Brightness temperature (TB) data collected at a ground resolution of 200m were employed to derive spatial distribution of surface soil moisture. Analysis of spatial and temporal soil moisture information in conjunction with soils data revealed a direct relation between changes in soil moisture and soil texture. A geographical information system (GIS) based analysis suggested that 2-days initial drainage of soil, measured from remote sensing, was related to an important soil hydraulic property viz. the saturated hydraulic conductivity (Ksat). A hydrologic modelling methodology was developed for estimation of Ksat of surface and sub-surface soil layers. Specifically, soil hydraulic parameters were optimized to obtain a good match between model estimated and field measured soil moisture profiles. Relations between 2-days soil moisture change and Ksat of 0-5 cm, 0-30 cm and 0-60cm depths yielded correla tions of 0.78, 0.82 and 0.71, respectively. These results are comparable to the findings of previous studies involving laboratory-controlled experiments and numerical simulations, and support their extension to the field conditions of the Little Washita watershed. These findings have potential applications of microwave remote sensing to obtain 2-days of soil moisture and then to quickly estimate the spatial distribution of Ksat over large areas. (author)

Effects of moisture, elevated temperature, and fatigue loading on the behavior of graphite/epoxy buffer strip panels with center cracks

Science.gov (United States)

Bigelow, C. A.

1988-01-01

The effects of fatigue loading combined with moisture and heat on the behavior of graphite epoxy panels with either Kevlar-49 or S-glass buffer strips were studied. Buffer strip panels, that had a slit in the center to represent damage, were moisture conditioned or heated, fatigue loaded, and then tested in tension to measure their residual strength. The buffer strips were parallel to the loading direction and were made by replacing narrow strips of the 0 deg graphite plies with Kevlar-49 epoxy or S-glass epoxy on a 1-for-1 basis. The panels were subjected to a fatigue loading spectrum. One group of panels was preconditioned by soaking in 60 C water to produce a 1 percent weight gain then tested at room temperature. One group was heated to 82 C during the fatigue loading. Another group was moisture conditioned and then tested at 82 C. The residual strengths of the buffer panels were not highly affected by the fatigue loading, the number of repetitions of the loading spectrum, or the maximum strain level. The moisture conditioning reduced the residual strengths of the S-glass buffer strip panel by 10 to 15 percent below the ambient results. The moisture conditioning did not have a large effect on the Kevlar-49 panels.

On the modulation of oxygen sensitivity of In{sub 2}O{sub 3} thin films: effects of moisture and dc bias

Energy Technology Data Exchange (ETDEWEB)

Zhu, Yihao; Koley, Goutam [Department of Electrical Engineering, University of South Carolina, Columbia, SC (United States)

2014-11-15

Oxygen sensing characteristics of In{sub 2}O{sub 3} thin film at room temperature have been investigated through conductivity measurements using interdigitated metal finger patterned devices. We observed that the O{sub 2} sensitivity gets affected very significantly in presence of moisture, as well as with applied dc bias. The O{sub 2} sensitivity was found to increase several times in moist ambient compared to dry ambient condition. Higher dc bias also dramatically improved the sensitivity, which varied more than two orders of magnitude as the dc bias was increased from 0.5 to 10 V. We propose that the observed increase in sensitivity in presence of moisture is caused by enhanced surface electron density on In{sub 2}O{sub 3} thin film resulting from the donation of electrons caused by the chemisorbed water molecules. The adsorption of O{sub 2} molecules, which subsequently formed O{sub 2}{sup -} ions, leads to chemical gating of the sensor devices, which under larger dc bias produced a higher fractional change in current leading to higher sensitivity. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Modeling moisture absorption kinetics of barley grain using viscoelastic model and neural networks

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M Kamali

2015-09-01

containers having 200 mg of distilled water. Grains were weighed after a predetermined period of elapsed time (5, 10, 15, 30, 60, 120, etc. minutes. The experiments were conducted with three replications and moisture absorption rates were determined by the equations presented by McWatters et al., 2002. The experiments were conducted on a time table based on which the time for the dissolving of grains was reached. In this case, the moisture content of the grains reaches the saturation point. According to equations presented by Peleg, as water density increases as much as 0.01 gram due to grains dissolving in water, the saturation point has been reached (Peleg, 1988. For this reason, distilled water density was measured and controlled before and after each experiment by a pycnometer. Neural network was designed according to the two methods of multi-layer perceptron (MLP and radial basis function (RBF with three neuron layers. The first layer, i.e. input layer, is independent variables of temperature and time.The second layer, i.e. hidden layers, is the networks hidden layer and the third layer, i.e. output layer, is the dependent variable of moisture content which was selected. In each case, the nonlinear reduced gradient, combined gradient and BFGS algorithm, and Trigonometric, Logarithmic, Gaussian, and Logical functions were used to train, test and evaluate the network. To evaluate the predicting viscoelastic model and the network, we used statistical indices maximum value of coefficient of determination (R2 and minimum value of mean square error (RMSE. Results and Discussion: Moisture absorption curves showed that as the temperature increases, moisture absorption rate increases as well. Higher equilibrium moisture levels are obtained in water with higher temperatures. This phenomenon is the result of increased moisture diffusion in grains due to higher temperature levels. Higher water temperatures causes grain internal material which is mainly starch to gelatinize and

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)

In-line moisture monitoring in fluidized bed granulation using a novel multi-resonance microwave sensor.

Science.gov (United States)

Peters, Johanna; Bartscher, Kathrin; Döscher, Claas; Taute, Wolfgang; Höft, Michael; Knöchel, Reinhard; Breitkreutz, Jörg

2017-08-01

Microwave resonance technology (MRT) is known as a process analytical technology (PAT) tool for moisture measurements in fluid-bed granulation. It offers a great potential for wet granulation processes even where the suitability of near-infrared (NIR) spectroscopy is limited, e.g. colored granules, large variations in bulk density. However, previous sensor systems operating around a single resonance frequency showed limitations above approx. 7.5% granule moisture. This paper describes the application of a novel sensor working with four resonance frequencies. In-line data of all four resonance frequencies were collected and further processed. Based on calculation of density-independent microwave moisture values multiple linear regression (MLR) models using Karl-Fischer titration (KF) as well as loss on drying (LOD) as reference methods were build. Rapid, reliable in-process moisture control (RMSEP≤0.5%) even at higher moisture contents was achieved. Copyright © 2017 Elsevier B.V. All rights reserved.

Complexation of rice starch/flour and maize oil through heat moisture treatment: Structural, in vitro digestion and physicochemical properties.

Science.gov (United States)

Chen, Xu; He, Xiaowei; Fu, Xiong; Zhang, Bin; Huang, Qiang

2017-05-01

This study investigated structural, in vitro digestion and physicochemical properties of normal rice starch (NRS)/flour (NRF) complexed with maize oil (MO) through heat-moisture treatment (HMT). The NRS-/NRF-MO complex displayed an increased pasting temperature and a decreased peak viscosity. After HMT, less ordered Maltese and more granule fragments were observed for NRS-/NRF-MO complex. Meanwhile, more aggregation was observed in the HMT samples with higher moisture contents. We found that higher onset temperature, lower enthalpy change and relative crystallinity of the NRS-/NRF-MO complex were associated with a higher moisture content of HMT samples. The higher moisture content of HMT was also favorable for the amylose-lipid complex formation. Differences in starch digestion properties were found for NRS-MO and NRF-MO complex. All of the NRS/NRF complexed MO after cooking showed lower rapidly digestible starch (RDS) contents compared with the control sample, therein NRS-/NRF- MO 20% exhibited the highest sum of the slowly digestible starch and resistant starch contents. In general, HMT had a greater impact on the in vitro digestion and physicochemical properties of flour samples compared with starch counterparts. Copyright © 2017 Elsevier B.V. All rights reserved.

Increasing Impact of Economic Conditions upon Higher Education Enrollments.

Science.gov (United States)

Rusk, James J.; And Others

1982-01-01

To assess the impact of economic conditions on enrollment in higher education, researchers used time series analysis on national data for 1966-78 and on 1972-78 data from all eight regions of the country and the University of Arizona. The findings indicate enrollment has gone up during economic downturns. (Author/RW)

A model for estimating time-variant rainfall infiltration as a function of antecedent surface moisture and hydrologic soil type

Science.gov (United States)

Wilkening, H. A.; Ragan, R. M.

1982-01-01

Recent research indicates that the use of remote sensing techniques for the measurement of near surface soil moisture could be practical in the not too distant future. Other research shows that infiltration rates, especially for average or frequent rainfall events, are extremely sensitive to the proper definition and consideration of the role of the soil moisture at the beginning of the rainfall. Thus, it is important that an easy to use, but theoretically sound, rainfall infiltration model be available if the anticipated remotely sensed soil moisture data is to be optimally utilized for hydrologic simulation. A series of numerical experiments with the Richards' equation for an array of conditions anticipated in watershed hydrology were used to develop functional relationships that describe temporal infiltration rates as a function of soil type and initial moisture conditions.

Soil Moisture Active Passive (SMAP) Mission Level 4 Surface and Root Zone Soil Moisture (L4_SM) Product Specification Document

Science.gov (United States)

Reichle, Rolf H.; Ardizzone, Joseph V.; Kim, Gi-Kong; Lucchesi, Robert A.; Smith, Edmond B.; Weiss, Barry H.

2015-01-01

This is the Product Specification Document (PSD) for Level 4 Surface and Root Zone Soil Moisture (L4_SM) data for the Science Data System (SDS) of the Soil Moisture Active Passive (SMAP) project. The L4_SM data product provides estimates of land surface conditions based on the assimilation of SMAP observations into a customized version of the NASA Goddard Earth Observing System, Version 5 (GEOS-5) land data assimilation system (LDAS). This document applies to any standard L4_SM data product generated by the SMAP Project. The Soil Moisture Active Passive (SMAP) mission will enhance the accuracy and the resolution of space-based measurements of terrestrial soil moisture and freeze-thaw state. SMAP data products will have a noteworthy impact on multiple relevant and current Earth Science endeavors. These include: Understanding of the processes that link the terrestrial water, the energy and the carbon cycles, Estimations of global water and energy fluxes over the land surfaces, Quantification of the net carbon flux in boreal landscapes Forecast skill of both weather and climate, Predictions and monitoring of natural disasters including floods, landslides and droughts, and Predictions of agricultural productivity. To provide these data, the SMAP mission will deploy a satellite observatory in a near polar, sun synchronous orbit. The observatory will house an L-band radiometer that operates at 1.40 GHz and an L-band radar that operates at 1.26 GHz. The instruments will share a rotating reflector antenna with a 6 meter aperture that scans over a 1000 km swath.

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

Spatial variability and its main controlling factors of the permafrost soil-moisture on the northern-slope of Bayan Har Mountains in Qinghai-Tibet Plateau

Science.gov (United States)

Cao, W.; Sheng, Y.

2017-12-01

The soil moisture movement is an important carrier of material cycle and energy flow among the various geo-spheres in the cold regions. It is very critical to protect the alpine ecology and hydrologic cycle in Qinghai-Tibet Plateau. Especially, it becomes one of the key problems to reveal the spatial-temporal variability of soil moisture movement and its main influence factors in earth system science. Thus, this research takes the north slope of Bayan Har Mountains in Qinghai-Tibet Plateau as a case study. The present study firstly investigates the change of permafrost moisture in different slope positions and depths. Based on this investigation, this article attempts to investigate the spatial variability of permafrost moisture and identifies the key influence factors in different terrain conditions. The method of classification and regression tree (CART) is adopted to identify the main controlling factors influencing the soil moisture movement. And the relationships between soil moisture and environmental factors are revealed by the use of the method of canonical correspondence analysis (CCA). The results show that: 1) the change of the soil moisture on the permafrost slope is divided into 4 stages, including the freezing stability phase, the rapid thawing phase, the thawing stability phase and the fast freezing phase; 2) this greatly enhances the horizontal flow in the freezing period due to the terrain slope and the freezing-thawing process. Vertical migration is the mainly form of the soil moisture movement. It leads to that the soil-moisture content in the up-slope is higher than that in the down-slope. On the contrary, the soil-moisture content in the up-slope is lower than that in the down-slope during the melting period; 3) the main environmental factors which affect the slope-permafrost soil-moisture are elevation, soil texture, soil temperature and vegetation coverage. But there are differences in the impact factors of the soil moisture in different

Significance of the air moisture source on the stable isotope composition of the precipitation in Hungary

Science.gov (United States)

Czuppon, György; Bottyán, Emese; Krisztina, Krisztina; Weidinger, Tamás; Haszpra, László

2017-04-01

In the last few years, the analysis of backward trajectories has become a common use for identifying moisture uptake regions for the precipitation of various regions. Hungary is influenced by meteorological (climatological) conditions of Atlantic, Mediterranean and North/East regions therefore this area is sensitive to detect changes in the atmospheric circulation. In this study we present the result of the investigation about the determination of air moisture source regions for six localities in Hungary for more than four years. To reconstruct the path of the air moisture from the source region, we ran the NOAA HYSPLIT trajectory model using the GDAS database with 1° spatial and 6 hours temporal resolution for every precipitation event, for heights of 500, 1500 and 3000 m. We determined the location where water vapour entered into the atmosphere by calculating specific humidity along the trajectories. Five possible moisture source regions for precipitation were defined: Atlantic, North European, East European, Mediterranean and continental (local/convective). Additionally, this study evaluates the regional differences in stable isotope compositions of precipitation based on hydrogen and oxygen isotope analyses of daily rainwater samples. Stable isotope variations show systematic and significant differences between the regions. The variability of moisture source shows also systematic seasonal and spatial distribution. Interestingly, the most dominant among the identified source regions in all stations is the Mediterranean area; while the second is the Atlantic region. The ratio of the precipitations originated in Eastern and Northern Europe seem to correlate with the geographic position of the meteorological station. Furthermore, the ratios of the different moisture sources show intra annual variability. In each location, the amount weighted d-excess values were calculated for the identified moisture sources. The precipitation originated in the Mediterranean

How crucial is it to account for the antecedent moisture conditions in flood forecasting? Comparison of event-based and continuous approaches on 178 catchments

Directory of Open Access Journals (Sweden)

L. Berthet

2009-06-01

Full Text Available This paper compares event-based and continuous hydrological modelling approaches for real-time forecasting of river flows. Both approaches are compared using a lumped hydrologic model (whose structure includes a soil moisture accounting (SMA store and a routing store on a data set of 178 French catchments. The main focus of this study was to investigate the actual impact of soil moisture initial conditions on the performance of flood forecasting models and the possible compensations with updating techniques. The rainfall-runoff model assimilation technique we used does not impact the SMA component of the model but only its routing part. Tests were made by running the SMA store continuously or on event basis, everything else being equal. The results show that the continuous approach remains the reference to ensure good forecasting performances. We show, however, that the possibility to assimilate the last observed flow considerably reduces the differences in performance. Last, we present a robust alternative to initialize the SMA store where continuous approaches are impossible because of data availability problems.

Multilayer moisture barrier