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ABSTRACT. Summer climatic moisture balances (precipitation--potential evapotranspiration) for topographic slopes favored by present-day xerophytic boreal grasslands (SSW aspects with 61%-65% gradients) in southwest Yukon were compared to their unglaciated late-Wisconsinan [...]

We deposited a silicon nitride (Si[N.sub.x])-polymer hybrid multilayer moisture barrier in a hot wire chemical vapor deposition (HWCVD) process, entirely below 100°C. The polymer, poly(glycidyl methacrylate) (PGMA), was deposited by initiated chemical vapour deposition and the Si[N.sub.x] in a dedicated HWCVD reactor. Line profile investigation of our barrier structures by cross-sectional scanning transmission electron microscopy and energy dispersive X-ray spectrometry reveals that, upon deposition of Si[N.sub.x] on top of our polymer layer, an intermediate layer of silicon oxide (Si[O.sub.x]) like material is formed. X-ray photoelectron spectroscopy measurements confirm the presence of this material and indicate the epoxy rings in the PGMA material open upon heating (to 100°C) and exposure to atomic hydrogen and amine species in the HWCVD process. The oxygen atoms subsequently react with silicon and nitrogen containing radicals to form Si[O.sub.x][N.sub.y]. The interlayer turns out to be highly beneficial for interlayer adhesion and this is considered to be one of the reasons for the excellent barrier properties of our multilayer. PACS Nos.: 68.60.Wm, 68.65.Ac, 66.30.jj. Resume : Nous deposons un pare-vapeur multicouche hybride de nitrure de silicium (Si[N.sub.x])/polymere par un procede de depot de vapeur chimique due a un filament chaud (HWCVD), le tout sous les 100°C. Le polymere, poly(methacrylate de glycidyle) (PGMA), est depose en vapeur chimique par activation et le Si[N.sub.x] dans un reacteur HWCVD dedie. Nous analysons les profiles de ligne de la structure de nos barrieres a l'aide de la microscopie electronique en transmission, avec balayage de la section efficace et par analyse X dispersive en energie. Cette analyse revele qu'en deposant Si[N.sub.x] sur le polymere, il se forme une couche intermediaire de materiau de type Si[O.sub.x]. Des mesures XPS confirment la presence de ce materiau et indiquent la presence de structures circulaires dans le PGMA lorsque chauffe a 100°C et expose a l'hydrogene atomique et a des amines durant le procede HWCVD. Les atomes d'oxygene reagissent alors avec le Si et les radicaux N pour former du Si[O.sub.x][N.sub.y]. Cette couche intermediaire s'avere benefique pour l'adhesion entre les couches et est consideree comme une des raisons pour les excellentes proprietes de pare-vapeur de notre multicouche., 1. Introduction Sensitive electronic devices can swiftly degrade because of oxygen and water vapor permeating into their active layers. For devices made on flexible plastic substrates, which, contrary to glass, [...]

The three-dimensional anisotropic moisture absorption behavior of quartz-fiber-reinforced bismaleimide (BMI) laminates is investigated by collecting 21 months of experimental gravimetric data. Laminates of six, twelve, and forty plies and various planar aspect ratios are used to determine the three-dimensional anisotropic diffusion behavior when exposed to full immersion in distilled water at 25°C. The long-term moisture absorption behavior deviates from the widely used Fickian model, but can be accurately captured by the three-dimensional, anisotropic hindered diffusion model (3D HDM). Excellent agreement is achieved between experimental gravimetric data and the 3D HDM for all laminate thicknesses. Recovered model parameters are shown to slightly vary with laminate thickness due to the small changes in the cured-ply thickness. However, model parameters identified for a given laminate thickness are observed to accurately predict the absorption behavior of samples with different planar dimensions. Equilibrium moisture content of 1.72, 1.69, and 1.84% and corresponding diffusion hindrance coefficients of 0.807, 0.844, and 0.671 are recovered for six, twelve, and forty-ply laminates, respectively, thus confirming strong non-Fickian behavior. Moisture absorption parameters may be determined successfully at 16.5 months of immersion, before reaching approximately 85% of the equilibrium moisture content at 21 months. Subsequent gravimetric measurements up to 21 months are consistent with the predicted long-term behavior. POLYM. ENG. SCI., 54:137-146, 2014. © 2013 Society of Plastics Engineers, INTRODUCTION Bismaleimide (BMI) is often used as the matrix material in composites expected to operate in extreme environmental conditions, such as high temperature and high humidity. BMI resins are widely [...]

This paper presents an integrated experimental-numerical approach to model the progressive moisture damage characteristics of bituminous paving mixtures. To this end, a Fickian model is utilized to determine the diffusion coefficient, which is a key property of simulating moisture transport causing moisture damage, and the semicircular bend (SCB) fracture tests are carried out to obtain the elastic stiffness and fracture properties at different levels of moisture conditioning. A sequentially coupled moisture diffusion and mechanical loading is implemented using a finite element method to model the progressive damage behavior due to the moisture transport followed by the mechanical loading. To simulate the fracture process as a gradual separation, a cohesive zone model is incorporated into the model. The integrated approach presented herein results in a degradation function that characterizes the progressive damage due to moisture uptake with two model parameters representing the remaining properties of materials and their degradation trend. These two model parameters can be used to estimate moisture damage mechanisms and damage resistance potential, both of which are material specific. Key words: bituminous paving mixtures, moisture damage, semicircular bend, fracture, cohesive zone. Cet article aborde l'approche integree experimentale-numerique pour modeliser les caracteristiques des dommages progressifs causes par l'humidite aux melanges de revetements bitumineux. Le modele de Fickian a donc ete utilise pour determiner le coefficient de diffusion, une propriete cle de la simulation du transport de l'humidite engendrant les dommages par humidite; des essais de flexion semi-circulaire a la rupture ont ete realises pour determiner la rigidite elastique et les proprietes des fractures a divers niveaux de conditionnement a l'humidite. Une charge mecanique couplee sequentiellement a la diffusion de l'humidite est implantee en utilisant une methode par elements finis afin de modeliser les dommages progressifs engendres par le transport de l'humidite, suivi par une charge mecanique. Un modele de la zone de cohesion est incorpore dans le modele afin de simuler le processus de fracturation en tant que separation graduelle. L'approche integree presentee produit une fonction de degradation caracterisant le dommage progressif cause par l'absorption d'humidite et dans laquelle deux parametres du modele representent les autres proprietes des materiaux et leur tendance a la degradation. Ces deux parametres de modele peuvent etre utilises pour evaluer les mecanismes de dommage par l'humidite ainsi que le potentiel de resistance aux dommages, qui sont tous deux specifiques au materiau. Mots-cles : melanges de revetement bitumineux, dommage par l'humidite, flexion semi-circulaire, fracture, zone de cohesion. [Traduit par la Redaction], Introduction Moisture infiltration into bituminous paving mixtures causes the progressive loss of structural integrity and eventually results in pavement failure. This phenomenon is known as moisture damage, one of the [...]

Traditionally, moisture damage in asphalt is determined by laboratory testing of liquid asphalt binder, loose mix, and (or) solid asphalt concrete samples under wet and dry conditions. Yet some asphalt mixes pass such laboratory moisture damage tests but show poor moisture damage potential in the field. To this end, this study presents asphalt constituents such as mastic and matrix testing for true evaluation of field moisture damage in asphalt concrete. Three mixes included in this study have almost identical laboratory moisture damage potential, but coarse mix (SP-III) has higher field moisture damage potential than two fine mixes (SP-B, SP-C). Related to these mixes, three mastics namely natural fines (NF), crushed fines (CF), and combined natural and crushed fines (NF+CF) are tested using a dynamic shear rheometer (DSR) at varying temperature and frequency. Also, matrix materials passing #4 sieve is tested in DSR, tension, pull-off, and direct shear loadings. It is shown that mastic and matrix test results can better identify field moisture damage of asphalt concrete. Fine mastic and matrix have low moisture damage potential than the coarse matrix and mastic. At high temperature (above 25 °C), shear modulus converges to a small number irrespective of mastic type. Due to moisture conditioning, matrix ultimate stress decreases in tension and pull-off tests but not in shear test. Key words: asphalt mastic, matrix, moisture damage, dynamic shear rheometer, tension, compression, shear modulus, binder, mixture. Les dommages causes a l'asphalte par l'humidite sont traditionnellement determines en laboratoire, par des essais sur des echantillons de liants routiers liquides, de melange en vrac et/ou de beton bitumineux solide sous des conditions humides et seches. Malgre cela, certains melanges d'asphalte passent avec succes de tels essais de resistance a l'endommagement par l'humidite mais montrent une pietre resistance a l'endommagement par l'humidite une fois sur le terrain. Ainsi, cette etude presente les composants de l' asphalte, tels que le mastic, et les essais matriciels pour une evaluation reelle des dommages causes par l' humidite au beton bitumineux sur le terrain. Trois melanges inclus dans cette etude presentaient un potentiel de resistance a l'endommagement par l'humidite presque identique lors des essais en laboratoire, mais le melange grossier (SP-III) presentait sur le terrain un potentiel de resistance a l'endommagement par l'humidite superieur a celui des deux melanges fins (SP-B et SP-C). Trois mastics, dont les fines naturelles (FN), les fines concassees (FC) et une combinaison de fines naturelles et concassees (FN+FC), ont ete mis a l'epreuve utilisant un rheometre de cisaillement dynamique (RCD) a differentes temperatures et frequences. De plus, tous les materiaux matriciels passant le tamis #4 ont ete mis a l'epreuve en tension, en arrachement, en cisaillement direct et en utilisant le DSR. Il est demontre que les resultats des essais sur les mastics et les produits matriciels peuvent mieux identifier les dommages causes au beton bitumineux par l'humidite sur le terrain. Les mastics et les produits matriciels fins presentent un potentiel de resistance a l'endommagement par l'humidite inferieur a celui de la matrice grossiere et du mastic. A une temperature elevee (au-dessus de 25 °C), le module de cisaillement converge vers un petit nombre, peu importe le type de mastic. En raison du conditionnement contre l'humidite, la contrainte a la rupture de la matrice diminue dans les essais en tension et en arrachement mais non dans les essais en cisaillement. Mots-cles : mastic d'asphalte, matrice, dommage par l'humidite, rheometre de cisaillement dynamique, tension, compression, module de cisaillement, liant, melange. [Traduit par la Redaction], 1. Introduction To date, numerous test methods have been developed and used to predict moisture-induced damage in asphalt concrete (Solaimanian et al. 1993; Cheng et al. 2002; Hicks et al. [...]

The objective of the research was to assess the structural capacity of reclaimed asphalt pavement (RAP) as a base layer and to investigate the effect of RAP content, moisture content (MC), freeze-thaw (F-T) conditioning, and dry density (DD) on the resilient modulus of untreated RAP as a base layer. The resilient modulus test was conducted in the laboratory for specimens containing different ratios of RAP and aggregate. All samples containing RAP had higher resilient modulus and lower permanent deformation compared to virgin aggregate. Resilient modulus of RAP decreased as the MC increased. At low MCs there was no clear effect of MC on permanent deformation. However, as moisture increased to the wet side of the optimum MC curve, loss of stability was clear. F-T conditioning did not have a negative impact on the stiffness of RAP; this was explained by the low ability of RAP/aggregate blends to hold moisture. DD effect on the resilient modulus was dependent on the level of MC, but developed models showed that increasing DD would increase MR at the same degree of saturation. DOI: 10.1061/(ASCE)MT.1943-5533.0000135 CE Database subject headings: Resilient modulus; Moisture; Freeze and thaw; Asphalt pavements; Sensitivity analysis. Author keywords: RAP; Base layer; Resilient modulus; Moisture sensitivity; Freeze-thaw.

Sesame (Sesamum indicum L) is one of the oldest cultivated plants. Its seed contains about 42-54% quality oil, 22-25% protein, 20-25% carbohydrates and 4-6% ash. This composition varies with genetic and environmental factors. Conditioning of oil seeds which include roasting, flaking, size reduction, cooking, pre-pressing and drying, is an important operation in the production line of sesame oil. This work investigated effects of initial moisture content, roasting duration and temperature on initial Peroxide Value (PV) and Oxidative Stability (OS) of un-refined sesame oil using response surface methodology. Goza-25, a variety of sesame seed that is commercially cultivated in Nigeria was used for the study. Initial moisture content levels were 4, 7, 10, 13 and 16% wet basis (wb). Roasting duration and temperature levels were 5, 10, 15, 20 and 25 minutes, and 50, 70, 90, 110 and 130 °C respectively. The recorded minimum and maximum PV were 3.9 and 15.4 meq/kg respectively. Mean value was 9.85 ± 3.9 meq/kg. Peroxide value increased with increasing moisture content and reduced with increasing roasting duration. Analysis of variance and regression analysis of obtained data showed that application of quadratic model to predict effect of initial moisture content, roasting duration and temperature on peroxide value is significant at p ≤ 0.05. Within the studied range, 13 h was the minimum OS recorded while maximum were 63.3 h. Mean of the data was 38.37 ± 16.02. Using the conversion factor of one hour of an active oxygen hour as being equivalent to 15 days; the expressed sesame oil in its present form will retain its quality for a maximum period of 949 days. Rise in roasting temperature and duration increased the oxidative stability, a reverse was observed with initial moisture content. High moisture content reduced the quality and storage life while heat treatment increased both the initial quality and storage life of the mechanically expressed oil. Peroxide value and oxidative stability of crude sesame oil significantly (p ≤ 0.05) depend on moisture content of the seed, roasting duration and temperature. Key words: Sesame, Oil, Crude, Oxidation, Storage, INTRODUCTION Sesame (Sesamum indicum L) also known as sesamum, gingelly, sim sim, beniseed and til is the one of the oldest cultivated plants [1]. Its seed contains about 42-54% quality [...]

Air dehydration of fruits has been reported to be limiting in some factors especially on the drying kinetics and quality of the dried fruits. Removal of moisture during drying is attributed to these. This study was designed to evaluate the effects of sulphiting and osmotic pretreatments on effective diffusion coefficient ([D.sub.eff]) of air drying pineapple slices at 50° and 70 °C temperatures. Smooth cayenne pineapple obtained from Ajanla farms, Ibadan, Nigeria was used for the study. The fruits were hand peeled and sliced to spherical slices of 5 cm radius and 0.5 cm thickness. Pineapple fruit slices were pretreated at three levels of sulphiting and sucrose/osmosis and two conditions of drying (50 °C at 16 h and 70 °C at 10 h), resulting in 18 treatments in a factorial experimental design. Changes in moisture were monitored hourly and Fick's second law was used to describe the rate of moisture transfer to determine the [D.sub.eff] as the slices were dried using a cabinet dryer. Results showed that the [D.sub.eff] was strongly affected by sulphiting at 2500 ppm equalling 9.10 ± 0.13 x [10.sup.-6] and 6.78 + 0.53 x [10.sup.-6] cm/s for 70 °C and 50 °C drying temperatures, respectively. The osmotic pretreatment at 40% sucrose recorded 4.91 ± 0.15 x [10.sup.-6] cm/s and 6.93 ± 0.03 x [10.sup.-6] cm/s for 70 °C and 50 °C drying temperature respectively. The control samples had 3.14 ± 0.23 x [10.sup.-6] and 4.19 ± 0.21 x [10.sup.-6] at 70 °C and 50 °C drying temperature, respectively. The high values obtained from the pretreated samples may be due to the restructuring of the cell walls. The combination of sulphiting and osmotic pretreatments also exhibited significant impact on the [D.sub.eff] value, ranging between 5.13 to 8.42 x [10.sup.-6], though not as pronounced as with the single pretreatment method. Furthermore, drying at 70 °C influenced the [D.sub.eff] value more than drying at 50 °C with both pretreatment methods. The study, therefore, showed that pretreatment methods improved the [D.sub.eff] of the pineapple slices, with the sulphiting pretreatment at 2500 ppm having the highest value. Key words: Sulphiting, osmotic, pretreatment, drying, kinetics, INTRODUCTION Air dehydration of fruits reportedly affects the quality of the dried fruits, though the method has been suggested as a way of developing dry fruit to alleviate huge fruit [...]

This paper presents a theoretical study of the effects of moist convection on geostrophic adjustment in an infinite channel. The governing equations correspond to a linearized shallow water system of equations for the atmosphere first vertical baroclinic mode, which is coupled to a vertically averaged moisture equation. The coupling is through a parameterization that represents precipitation. The transient behavior and final state of the flow initially at rest with active precipitation limited to half of the channel is investigated, both numerically and analytically. It is shown that an initial imbalance resulting from precipitation induces a circulation that dries out the nonprecipitating region and further enhances precipitation. This interaction between precipitation and dynamics leads to a sharper temperature gradient and stronger jet in the final state, when compared to the dry adjustment. Unlike in the dry case, the moist geostrophic adjustment cannot be entirely determined from the initial unbalanced flow, since it depends on the time scale for convection. Analytic approximations are derived in limits of both fast and slow convective adjustment time. DOI: 10.1175/2010JAS3405.1

A theoretical framework is developed for the evolution of baroclinic waves with latent heat release parameterized in terms of vertical velocity. Both wave-conditional instability of the second kind (CISK) and large-scale rain approaches are included. The new quasigeostrophic framework covers evolution from general initial conditions on zonal flows with vertical shear, planetary vorticity gradient, a lower boundary, and a tropopause. The formulation is given completely in terms of potential vorticity, enabling the partition of perturbations into Rossby wave components, just as for the dry problem. Both modal and nonmodal development can be understood to a good approximation in terms of propagation and interaction between these components alone. The key change with moisture is that growing normal modes are described in terms of four counter-propagating Rossby wave (CRW) components rather than two. Moist CRWs exist above and below the maximum in latent heating, in addition to the upper- and lower-level CRWs of dry theory. Four classifications of baroclinic development are defined by quantifying the strength of interaction between the four components and identifying the dominant pairs, which range from essentially dry instability to instability in the limit of strong heating far from boundaries, with type-C cyclogenesis and diabatic Rossby waves being intermediate types. General initial conditions must also include passively advected residual PV, as in the dry problem. DOI: 10.1175/2010JAS3410.1

Building stones are porous media and they can deteriorate through moisture ingress and secondary damage such as crystallization of soluble salts. Not only is this due to the increasing number of flood events in the past years but also structural damages of houses from activity such as leakage or rising moisture (groundwater) are the main causes. The potential benefit of several nondestructive testing methods to assess water damage in building stone has been studied in a field-scale experiment. Three testing walls made of fired clay brick, sandstone, and spongilite were flooded and their drying behavior monitored using infrared thermography, complex resistivity, ground penetrating radar, and ultrasonics. The results were compared to the average moisture content determined by gravimetric weighing of the specimens. Qualitatively, the results of the different nondestructive testing methods matched well. But in terms of quantitative data, some scatter was observed and the results should be viewed with care. Collecting time-consuming calibration data would help to overcome this problem, but especially when dealing with historic building structures, this is not always possible in practice. DOI: 10.1061/(ASCE)CF.1943-5509.0000056 CE Database subject headings: Diagnosis; Moisture; Masonry; Nondestructive tests. Author keywords: Diagnostics; Moisture; Masonry; Nondestructive tests; Electrical.

The role of environmental moisture in the deepening of cumulus convection is investigated by means of cloud-resolving numerical experiments. Under idealized conditions of uniform SST and specified radiative cooling, the evolution of trade wind cumulus into congestus clouds, and ultimately deep convection, is simulated and analyzed. The results exhibit a tight coupling between environmental moisture and cloud depth, both of which increase over the course of the simulations. Moistening in the lower troposphere is shown to result from the detrainment of water vapor from congestus clouds, and the strength of this tendency is quantified. Moistening of the lower troposphere reduces the dilution of cloud buoyancy by dry-air entrainment, and the relationship between this effect and increasing cloud depth is examined. The authors confirm that the mixing of water vapor by subgrid-scale turbulence has a significant impact on cloud depth, while the mixing of sensible heat has a negligible effect. By contrast, the dependence of cloud depth on CAPE appears to be of secondary importance. However, the deepening trend observed in these simulations is not solely determined by the evolving mean vapor profile. While enhancing the horizontally averaged humidity does result in deeper clouds, this occurs only after an adjustment period of several hours, presumably because of the buildup of CAPE. The implications of these findings for large-scale simulations in which resolved mixing is reduced--for example, by coarser spatial resolution or 2D experiments--are also discussed. DOI: 10.1175/2010JAS3357.1

The moisture damage in polymer modified asphalts has been studied for decades, yet the effects of chemical functional groups on moisture sensitivity are not known. In this study, a nanoscale experiment is conducted to measure these effects in terms of adhesive/ cohesive forces using an atomic force microscopy (AFM). A base asphalt binder and two polymers such as styrene-butadiene (SB) and styrene-butadiene-styrene (SBS) modified asphalts are used to prepare an AFM sample on glass substrates. The AFM samples are conditioned under dry and wet conditions. In the AFM, these samples are probed by silicon nitrite (Si3N4), carboxyl (--COOH), methyl (--CH3), and hydroxyl (--OH) functionalized AFM tips and nanoscale pull-off or adhesion/cohesion forces between asphalt and tip molecules are measured. Based on the ratio of wet to dry adhesion/cohesion forces, it is shown that the polymer modification makes binders less susceptible to moisture damage. Among the four tips, the --COOH tip shows almost no difference in adhesion forces between wet and dry samples. Using--OH tips, it is shown that the cohesion in SBS modified wet asphalt samples is significantly higher than the cohesion in SB modified wet asphalt samples. The Si3N4 tip shows higher adhesion in SB modified wet samples than that in the SBS polymer modified wet samples. Based on the adhesion/cohesion force, 3% polymer is found to be the optimum for both SB and SBS polymers. In addition, this study determines the methodology for sample preparation and testing parameters for nanoscale AFM testing on asphalt binders. DOI: 10.1061/(ASCE)MT.1943-5533.0000072 CE Database subject headings: Microscopy; Moisture; Damage; Roughness; Polymer; Asphalts. Author keywords: Atomic force microscopy; Adhesion; Cohesion: Moisture damage; Roughness; Nanoscale; Polymer modified asphalts; Functionalized tips.

Moisture-induced damage has long been recognized as one of the major concerns for asphalt pavements. To mitigate potential moisture damage, one general method is to add mineral antistripping additives or liquid antistripping agents into hot-mix asphalt (HMA) mixtures. In this study, a comparative laboratory experiment was conducted to investigate the effectiveness of cementitious fillers on moisture susceptibility of HMA mixtures. Five types of cementitious fillers were considered: fly ash, cement kiln dust, and three types of hydrated lime with different finenesses. The laboratory performance of HMA mixtures subjected to moisture conditioning was evaluated through the following tests: dynamic modulus test; superpave indirect tensile tests; and tensile strength ratio test. The test results indicate that the cementitious fillers were generally effective in reducing the moisture susceptibility of HMA mixtures. The finer the hydrated lime particle, the more resistant the asphalt mixtures. In addition, dynamic shear rheometer test was conducted on asphalt mastics to explore the stiffening effect of different cementitious fillers. DOI: 10.1061/(ASCE)MT.1943-5533.0000064 CE Database subject headings: Moisture; Damage; Cements; Fills; Stiffening; Asphalts; Laboratory tests. Author keywords: Moisture damage; Cementitious filler; Fineness; Stiffening effect.

The study of heat and moisture flows in multiple layers of different materials that make up the unsaturated zone is of great importance when characterizing the behaviour of these materials. In the present paper, analytical solutions of the one-dimensional heat and moisture coupled diffusion problem for layered materials under two different sets of boundary conditions are proposed. The coupled flow of heat and moisture are assumed to follow the theory of Philip and De Vries, and the solutions are derived analytically using integral transform methods. A comparison between the analytical and numerical solutions for one example problem shows satisfactory results. Furthermore, a procedure is presented for estimating heat and moisture distribution profiles in any layered materials using the derived analytical solutions. It is expected that the proposed analytical solutions will be used effectively for preliminary analyses of coupled heat and moisture movements in unsaturated porous media. Key words: heat and moisture coupled diffusion problem, layered materials. Lors de la caraclerisation du comporiemeni de differenls materiaux qui composent la zone non saturee, l'etude de l'ecoulement de la chaleur et de l'humidite dans les couches multiples de ces materiaux est particulifiremeni importante. Dans cet article, nous proposons des solutions analytiques pour la diffusion unidimensionnelle de la chaleur et de l'humidite de facon couplee pour des materiaux ayant plusieurs couches et sous deux types de conditions frontieres differentes. L'ecoulement couple de la chaleur et de l'humidite suit la theorie de Philip et De Vries et les solutions sont derivees de facon analytique a l'aide de methodes de transformation d'integrales. Les resultats d'un exemple de probleme obtenus a l'aide des solutions analytiques et numeriques ont ete compares, et la comparaison s'est averee satisfaisante. De plus, une procedure est presentee permettant d'estimer les profils de distribution de la chaleur et de I'humidite dans un materiau a plusieurs couches a l'aide des solutions analytiques derivees. Les solutions analytiques proposees pounonl eire utilisees dans les analyses preliminaires des mouvements couples de chaleur et d'humidite dans les milieux poreux non satures. Mots-cles : probleme de diffusion couplee de chaleur et d'humidite, materiaux a couches. [Traduit par la Redaction], Introduction The coupled processes of heat transfer and moisture movement in unsaturated materials are of interest to many scientists and engineers in the fields of soil physics, agricultural science, rock [...]

Dry, windy weather conditions during harvest can lead to very low seed-moisture content and severe soybean [Glycine max (L.) Merr.] seed germination problems. Some low-moisture content seed lots have particularly low and highly variable standard germination test results, presumably caused by imbibitional injury. The objectives of this study were to evaluate the influence of seed moisture content and seed composition on germination in the laboratory and field, and to evaluate standard germination test protocols for testing low-moisture content soybean seeds. Commercial seed lots of different seed composition were equilibrated to 0.07, 0.08, and 0.12 g [H.sub.2]O/g fw. Four official testing media were used in the experiments: rolled paper towels (T), crepe cellulose paper (C), crepe cellulose paper covered with sand (CS), and sand germination (S). Soybean germination and emergence were affected by maturity group, seed composition, and field conditions at planting. The testing medium and seed moisture content also influenced germination in the laboratory, but seed moisture content did not affect field emergence. These results suggest that soybean imbibitional injury caused by low-moisture seed lots occurs primarily in the laboratory. Seed analysts must consider soybean seed composition, moisture content, and their interaction with testing media when testing low-moisture content soybeans in the laboratory.

Observations show that convective perturbations of the tropical atmosphere are associated with substantial variations of clouds and water vapor. Recent studies suggest that these variations may play an active role in the large-scale organization of the tropical atmosphere. The present study investigates that possibility by using a two-dimensional, nonrotating model that includes a set of physical parameterizations carefully evaluated against tropical data. In the absence of cloud--radiation interactions, the model spontaneously generates fast upwind (eastward) moving planetary-scale oscillations through the wind-induced surface heat exchange mechanism. In the presence of cloud--radiative effects, the model generates slower upwind (eastward) propagating modes in addition to small-scale disturbances advected downwind (westward) by the mean flow. Enhanced cloud--radiative effects further slow down upwind propagating waves and make them more prominent in the spectrum. On the other hand, the model suggests that interactions between moisture and convection favor the prominence of moist Kelvin-like waves in tropical variability at the expense of small-scale advective disturbances. These numerical results, consistent with theoretical predictions, suggest that the interaction of water vapor and cloud variations with convection and radiation plays an active role in the large-scale organization of the tropical atmosphere.

Future climate change is expected to have many impacts on forest ecosystems. It is important to have some understanding of these impacts in order to make informed forest management decisions. A major consideration in making forest management decisions is the productivity of a site, as measured by site index. In this study, I relate Douglas-fir site index to accumulated growing degree-days greater than 5[degrees]C (DD5), as well as to soil moisture and nutrient regime. This allows the impact of climate change on forest productivity to be estimated. A two step approach was followed. The first step derived models to estimate various climate variables to latitude, longitude, and elevation using data from climate stations. Then, these climate variables were used along with soil moisture and nutrient data to predict site index for the site index plots. A two step approach was taken because climatic data were not available for the site index plots. The trend was for site index to increase with both increasing soil moisture and nutrients, although the site index decreased on the wetter sites. Site index also increased with DD5 at the rate of 1.2 m for every increase of 100 units in DD5. These models can be used together to evaluate the impact of various climate change scenarios on site index.

Moisture is transported in South America westward from the tropical Atlantic Ocean to the Amazon basin, and then southward toward the extratropics. A regional intensification of this circulation to the east of the Andes Mountains is called the South American low-level jet (SALLJ), with the strongest winds found over eastern Bolivia. SALLJ is present all year and channels moisture to the La Plata basin, which is analogous to the better-known Amazon basin in terms of its biological and habitat diversity, and far exceeds the latter in its economic importance to southern and central South America in terms of hydroelectricity and food production. The relatively small SALLJ spatial scale (compared with the density of the available sounding network) has a limited understanding of and modeling capability for any variations in the SALLJ intensity and structure as well as its possible relationship to downstream rainfall. The SALLJ Experiment (SALLJEX), aimed at describing many aspects of SALLJ, was carried out between 15 November 2002 and 15 February 2003 in Bolivia, Paraguay, central and northern Argentina, western Brazil, and Peru. Scientists, collaborators, students, National Meteorological Service personnel, and local volunteers from South American countries and the United States participated in SALLJEX activities in an unprecedented way, because SALLJEX was the most extensive meteorological field activity to date in subtropical South America, and was the first World Climate Research Program/ Climate Variability and Prediction Program international campaign in South America. This paper describes the motivation for the field activity in the region, the special SALLJEX observations, and SALLJEX modeling and outreach activities. We also describe some preliminary scientific conclusions and discuss some of the remaining questions

A study was conducted, using nuclear magnetic resonance (NMR) micro imaging, to examine the moisture distribution and oil distribution in tempura coating. The result reveals a three-layered fine structure of the tempura coating on these NMR images.

A three-dimensional model for stiffness and hygroexpansion of fiber and particle composite materials is presented. The model is divided into two steps, first a homogenization of a single fiber with a coating representing the matrix material, then a network mechanics modeling of the assembly of coated fibers that constitutes the composite material. The network modeling is made by a fiber orientation integration including a linear and an exponential interpolation between the extreme case of homogenous strain and the extreme case of homogenous stress. A comparison between the modeled prediction and measurement data is made for stiffness, Poissons ratio, and hygroexpansion. The matrix material is assumed to have isotropic properties and the fiber or particle material may have arbitrary orthotropic properties. CE Database keywords: Three-dimensional models; Stiffness; Composite materials; Wood; Fibers.

Biofilters do not provide much water for bacteria to grow. To use them efficiently and properly, it is essential to understand the kinetics of water transformation and to control moisture [...]

A new approach is presented to quantify upper-level moisture transport from geostationary satellite data. Daily time sequences of Geostationary Operational Environmental Satellite GOES-7 water vapor imagery were used to produce estimates of winds and water vapor mixing ratio in the cloud-free region of the upper troposphere sensed by the 6.7-(mu)m water vapor channel. The winds and mixing ratio values were gridded and then combined to produce a parameter called the water vapor transport index (WVTI), which represents the magnitude of the two-dimensional transport of water vapor in the upper troposphere. Daily grids of WVTI, meridional moisture transport, mixing ratio, pressure, and other associated parameters were averaged to produce monthly fields for June, July, and August (JJA) of 1987 and 1988 over the Americas and surrounding oceanic regions. The WVTI was used to compare upper-tropospheric moisture transport between the summers of 1987 and 1988, contrasting the latter part of the 1986/87 El Nino event and the La Nina period of 1988. A similar product derived from the National Centers for Environmental Prediction (NCEP)-National Center for Atmospheric Research (NCAR) 40-Year Reanalysis Project was used to help to validate the index. Although the goal of this research was to describe the formulation and utility of the WVTI, considerable insight was obtained into the interannual variability of upper-level water vapor transport. Both datasets showed large upper-level water vapor transport associated with synoptic features over the Americas and with outflow from tropical convective systems. Minimal transport occurred over tropical and subtropical high pressure regions where winds were light. Index values from NCEP-NCAR were 2-3 times larger than that determined from GOES. This difference resulted from large zonal wind differences and an apparent overestimate of upper-tropospheric moisture in the reanalysis model. A comparison of the satellite-derived monthly values between the summers of 1987 and 1988 provided some insight into the impact of the ENSO event on upper-level moisture and its transport during the period. During July 1987, a large portion of the Tropics in the eastern Pacific Ocean and Caribbean Sea was dominated by strong vapor transport in excess of 4.0 g kg(super -1) m s(super -1), with relatively small amounts in the other months. JJA 1988 transport values reached similar magnitude and showed similar patterns for all three months. The meridional transport of upper-level water vapor indicated large poleward transport from the Tropics to the higher latitudes. This transport favored the Southern Hemisphere, with large transport occurring south of the ITCZ, which extended across the eastern Pacific and northern South America. Zonally averaged monthly transport values were shown to provide a simple way to quantify the monthly and interannual changes in water vapor transport. Zonally averaged WVTI values peaked in the Southern Hemisphere subtropics during both austral winters. In the Tropics, a single, more pronounced peak located over the equator and south latitudes occurred in 1988 as opposed to a dual peak in 1987. The second peak around 20 degrees N latitude is consistent with findings of others in which upper-tropospheric winds were noted to be stronger in this region during warm ENSO events. Zonally averaged meridional transport was southward for all summer months and was stronger in 1988. The asymmetric nature of the zonally averaged meridional transport (more southerly water vapor transport) was enhanced during JJA 1988, thus indicating a stronger upper-level branch of the Hadley circulation during this notably strong La Nina period.

To improve the accuracy of vertical profiles of temperature and moisture retrieved from infrared spectral measurements, the surface emissivity must be accounted for in the solution of the inverse problem (based upon the radiative transfer equation). A model that accounts for the emission and reflection on the lower atmospheric boundary and an algorithm of solution are presented. Results using spectral measurements from an airborne radiometer over land surfaces are discussed. The solution of the inverse problem includes the surface emissivity, the surface temperature, and the vertical temperature-humidity profile. It is shown that accounting for the surface emissivity in the solution of the inverse problem substantially and positively changes the meteorological profiles.

Byline: L.C. Gutkoski (1), A.A. El-Dash (2) Keywords: Extrusion; Moisture; Oats (Avena sativa L.); Temperature Abstract: The purpose of this research was tostudy the effects of initial moisture levels andextrusion temperatures on bulk density, waterabsorption and water solubility indexes, viscosity,and color of extruded oat products. The dehulledgrains were ground in a Brabender Quadrumat Seniormill and the coarse fraction, with higher amounts ofcrude protein, lipids, and dietary fiber content, wereconditioned to moisture levels of 15.5--25.5% andextruded in a Brabender single-screw laboratoryextruder. The water absorption index of extrudateswere relatively low (4.16--6.35 g gel/g sample) butincreased as the initial moisture of the raw materialas well as the extrusion temperature was elevated.The water solubility index was inversely proportionalto the extrusion temperature. Initial viscosity of thepaste increased with the increase of raw materialmoisture and extrusion temperature, while the maximumviscosity (at a constant temperature) diminished withthe increase of temperature. Products with lowervalues of L* (luminosity) and greater values ofa* (red) and b* (yellow) were obtained athigh moisture rates and at a 120 deg.sup.C extrusiontemperature. Author Affiliation: (1) College of Agriculture and Veterinary Medicine, University of Passo Fundo, UPF, Passo Fundo -- RS, Brazil (2) College of Food Engineering, UNICAMP, Campinas -- SP, Brazil Article History: Registration Date: 30/09/2004

The role of humidity on the rate of removal of single crystal NaCl particles from a glass substrate by using the tip of a scanning force microscope (SFM) under controlled atmospheres of known humidity has been studied. Results indicate that only the smallest particles can be removed by the SFM tip when the relative humidity (RH) is 3%. However, larger particles can be removed when RH is increased to 30%. The stress needed in removing the particles is inversely proportional to the square root of the particle area.

The moisture level in biomass fuels potentially impacts efficiency in conversion to power. This paper examines the efficiency and net power output of a fluidized bed gasifier-combined cycle with flue gas drying for a range of as-received raw biomass moisture contents and levels of pregasification drying. Due to the lack of empirical data available, a modeling approach is used to simulate the effect of varying moisture content in the gasifier feed biomass. For a specified as-received biomass moisture content, drying prior to gasification increases overall efficiency', but the gains in efficiency decrease with increasing levels of drying. For a specified post-dryer gasifier feed moisture content, cycle efficiency and power output increase with decreasing as-received biomass moisture down to 30 percent, below which the change in cycle performance is negligible.

Research was conducted to examine the effects of glass transition and water activity on glycine loss rate constants resulting from the Maillard reaction in reduced-moisture model systems. Quantification of brown pigment development and glycine loss was done during storage at 25 degrees C. Results demonstrate that the physical characteristics of the matrix affect the kinetics of glycine loss through the Maillard reaction.

Recent theoretical studies have indicated that large-scale circulation in deep convective regions evolves subject to an overall static stability - termed the gross moist stability - that takes into account both dry static stability and moist convective effects. The gross moist stability has been explicitly defined for a continuously stratified atmosphere under convective quasi-equilibrium constraints. A subsidiary quantity - the gross moisture stratification - measures the overall effectiveness in producing precipitation subject to these quasi-equilibrium constraints. These definitions are relevant in regions that experience deep convection sufficiently often; criteria based on climatological precipitation and maximum level of convection are used to define a domain of applicability. In this paper, 10-yr monthly mean rawinsonde data, and European Centre for Medium-Range Weather Forecasts (ECMWF) and National Meteorological Center (NMC) analyses are used to estimate the magnitude and horizontal distribution of these two quantities in the Tropics within the domain of applicability. The gross moist stability is found to be positive but much smaller than typical dry static stability values. Its magnitude varies modestly from 200 to 800 J [kg.sup.-1] and exhibits relatively little dependence on sea surface temperature (SST). These values correspond, for instance, to a phase speed change from 8 to 16 m [s.sup.-1] for the Madden-Julian oscillation. The gross moisture stratification is larger and exhibits strong dependence on SST, varying from 1500 to 3500 J [kg.sup.-1] between cold and warm SST regions. A high degree of cancellation between effects of increasing low-level moisture and maximum level of convection, respectively, tends to keep the gross moist stability values relatively constant. Differences among the ECMWF and NMC analysis products and the rawinsonde data affect the estimate, but there is qualitative agreement. It is encouraging that reasonably robust estimates of a small, positive gross moist stability (as the difference between larger dry static stability and gross moisture stratification quantities) can be obtained. This helps justify use of small, constant moist phase speeds in some simple models of tropical circulation, although it also points out inconsistencies in how such models neglect variations in the height of convection.

The effects of different moisture distributions on the generation of moist potential vorticity (MPV) in extratropical cyclones are examined by numerical simulations. These sensitivity experiments show that low-level negative MPV generation depends on the initial distribution of potential temperature and moisture gradients. The generation of negative MPV depends on the baroclinic and moisture gradient vectors. It can also depend on the locations of condensation. Although condensation has no direct effect on MPV production, MPV can be generated in the neighborhood of condensation where the gradients of potential temperature and moisture have significantly changed. It is found in the sensitivity experiments that the bent-back warm front is the most favored regions for negative MPV generation because strong deformation of moisture and potential temperature fields occur. After the cyclones mature, negative MPV moves into the warm core. It can be transported upward through the enhanced vertical motion induced by latent heat release.

A study was conducted on the moisture weight gain or loss in plastic ball grid array (PBGA) packages as a function of time, including the effects of material selection and package geometry. Experimental weight gain and bake-out results for a 68 I/O PBGA package closely approximates the finite element analysis model predictions. Diffusivity and solubility property data for common packaging materials are shown as a function of temperature from 23 to 210 degrees Celsius.

Activated carbon has long been used for removal or recovery of volatile organic compounds (VOCs) from exhaust gas streams. Moisture content in the gas streams has been shown to be unfavorable for adsorption of VOCs; however, limited quantitative models were found in the literature. This paper reports experimental data and proposes a model concerning the effect of moisture on the adsorption capacities of a granular activated carbon (GAC) for cyclohexane and normal hexane in air streams with relative humidities (RHs), equilibrium temperatures, and VOC concentrations in the ranges of 0-0.9, 33.6-76.4 [degrees] C, and 500-3,000 ppmv, respectively. Results show that within the experimental conditions the adsorption capacities of the GAC for the VOCs both in humid and dry air streams can be related to vapor pressures of the VOCs by the Langmuir model. Effect of RH on the VOC adsorption capacities are related to RHs of the air streams by the Freundlich-like model: [q.sub.VOC]/[q.sub.VOC, RH=0] = 1 - kR[H.sup.1/n]. Some literature-cited data are also shown to be fit to the proposed model.

The moisture content influences the gel properties of the surimi from pollock, Pacific herring, arrowtooth flounder and Pacific whiting. An increase in the moisture content decreases the torsion stress and strain. Moisture content has a greater influence on the torsion strain values, than on the stress values. Punch test results are less consistent than the torsion test results. Mathematical adjustment is possible for shear stress and strain values of surimi from different species. However, correction factors are necessary for surimi samples containing protease inhibitors.

The stability of equatorial Rossby waves in the presence of mean flow vertical shear and moisture convergence-induced heating is investigated with a primitive equation model on an equatorial [Beta] plane. A vertical shear alone can destabilize equatorial Rossby waves by feeding mean flow available potential energy to the waves. This energy transfer necessitates unstable waves' constant phase lines tilt both horizontally (eastward with latitude) and vertically (against the shear). The preferred most unstable wavelength increases with increasing vertical shear and with decreasing heating intensity, ranging typically from 3000 to 5000 km. The instability strongly depends on meridional variation of the vertical shear. A broader meridional extent of the shear allows a faster growth and a less-trapped meridional structure. When the shear is asymmetric relative to the equator, the unstable Rossby wave is constrained to the hemisphere where the shear is prominent. Without boundary layer friction the Rossby wave instability does not depend on the sign of the vertical shear, whereas in the presence of the boundary layer, the moist Rossby wave instability is remarkably enhanced (suppressed) by easterly (westerly) vertical shears. This results from the fact that an easterly shear confines the wave to the lower level, generating a stronger Ekman-pumping-induced heating and an enhanced meridional heat flux, both of which reinforce the instability. The moist baroclinic instability is a mechanism by which westward propagating rotational waves (Rossby and Yanai waves) can be destabilized, whereas Kelvin waves cannot. This is because the transfer of mean potential energy to eddy requires significant magnitude of barotropic motion. The latter is a modified Rossby wave and can be resonantly excited only by the westward propagating rotational waves. The common features and differences of the equatorial Rossby wave instability and midlatitude baroclinic instability, as well as the implications of the results are discussed.

Examination of conditional instability of the second kind (CISK) and wind-induced surface heat exchange (WISHE), two proposed mechanisms for tropical cyclone and polar low intensification, suggests that the sensitivity of the intensification rate of these disturbances to surface properties, such as surface friction and moisture supply, will be different for the two mechanisms. These sensitivities were examined by perturbing the surface characteristics in a numerical model with explicit convection. The intensification rate was found to have a strong positive dependence on the heat and moisture transfer coefficients, while remaining largely insensitive to the frictional drag coefficient. CISK does not predict the observed dependence of vortex intensification rate on the heat and moisture transfer coefficients, nor the insensitivity to the frictional drag coefficient since it anticipates that intensification rate is controlled by frictional convergence in the boundary layer. Since neither conditional instability nor boundary moisture content showed any significant sensitivity to the transfer coefficients, this is true of CISK using both the convective closures of Ooyama and of Charney and Eliassen. In comparison, the WISHE intensification mechanism does predict the observed increase in intensification rate with heat and moisture transfer coefficients, while not anticipating a direct influence from surface friction.

Upper-air budget methods can be used to estimate the surface sensible and latent heat flux densities on a regional scale. This study assesses the application of radiosonde-based budget methods above homogeneous cropland. Serial daytime soundings were released from Kenaston and Saskatoon, Canada, on fair-weather days between 24 June and 31 July 1991. Two independent methods were used to establish ground truth: surface-layer Bowen ratio-energy balance and Priestley-Taylor. This study was the first to extend the surface-layer Bowen ratio method to conventional upper-air soundings. The two ground-truth methods agreed to within 20% at both locations and gave mean daytime Bowen ratios of 0.33. The upper-air budget surface flux estimates agreed most consistently with ground truth when the budget was integrated over the atmospheric boundary layer (BL) and used parameterized entrainment with a value for the entrainment parameter [A.sub.R] of 0.4. The BL budget with [A.sub.R] of 0.4 closed the daytime surface energy balance to within 4% at Kenaston and 7% at Saskatoon and gave a mean estimate for the Bowen ratio that agreed to within 20% of the mean ground-truth estimates. However, the BL budget estimates for 2-3-h periods were quite variable, and it was necessary to average the budget estimates over periods of 12 days or longer to produce credible values. Random sampling errors and uncertainty in horizontal advection were partly responsible for the high variability of the budget estimates, but these terms averaged to zero over extended periods. More seriously, the BL budget estimates for the surface latent heat flux were quite sensitive to the method for estimating entrainment. Because the authors were unable to establish a preferred entrainment estimate a priori, the BL budget estimates for the surface latent heat flux were considered to be unreliable. Further study is needed to develop a reliable and independent method for specifying the value for [A.sub.R].

Experiments have assessed how moisture and heat influence the functional and structural integrity of butyl rubber matrix composites used as protective barriers. This paper, which is first of a series, reports the findings on the subjects of moisture diffusion and its effect on ultrasonic wave propagation of composite barriers. On exposure to high humidity at elevated temperatures, carbon black-reinforced butyl rubber composite barriers were found to absorb substantial moisture, with the hygroscopic reinforcement phase making a more significant contribution than the matrix. The moisture diffusion coefficients for both composite and unreinforced vulcanizate were close to each other at each exposure temperature, and had the same temperature dependence. The calculated activation energies of moisture diffusion indicate that the moisture absorption rate of the carbon black phase is governed by the moisture diffusion rate of the matrix. Ultrasonic wave speed appeared to be a viable means of monitoring the moisture absorption of composite barriers. On exposure to moist heat, relative ultrasonic wave speeds for both composite and unreinforced vulcanizate decreased continuously., INTRODUCTION Elastomer-based composites have been extensively utilized and considered for utilization in a variety of barrier applications [1-7]. Examples are personal protective clothing in work places dealing with chemicals, pesticides, [...]

Several workers have demonstrated the presence of singular stress fields near the edge of a bimaterial interface subject to thermal gradients. Many of the analyses in the literature are limited to linear elastic materials and are useful as first estimates of stresses in such assemblies. However, a time-dependent stress analysis is necessary when viscoelastic materials such as polymer films are bonded to elastic substrates. This paper shows the relevance of viscoelastic modeling in demonstrating the effects of combined temperature and moisture loading on bimaterial interfaces and viscoelastic films sandwiched between elastic substrates. A 2-D finite element method for linear hygrothermoviscoelasticity based on an incremental creep strain rate form is developed. The correspondence principle of linear viscoelasticity is invoked and comparisons between FEA and analytical solutions are demonstrated. Moisture is modeled using Fick's law and the thermorheologically simple material (TSM) postulate is extended to incorporate a moisture shift function in analogy with temperature. The analysis of a polyimide film sandwiched between elastic substrates subject to a thermal cycle with diffusion from the free edge shows stress reversals for the peel stresses that may explain failure modes not anticipated by an elastic analysis.

Injection molded short glass fiber reinforced poly(butylene terephthalate) was subjected to hygrothermal aging at two different relative humidities--81.2% and 100% RH. A single free phase model of diffusion has been used to analyze the data obtained from the kinetics of moisture absorption study. The diffusion coefficient and the equilibrium moisture content were found to be dependent on the volume fraction of fibers and relative humidity. Incorporation of short glass fibers into a poly(butylene terephthalate) matrix has led to a significant improvement in the retention and recoverability of the tensile properties. Examination of fracture surfaces using a scanning electron microscope (SEM) has revealed some evidence for the hydrolysis of the polymer matrix. The hydrolysis resulted in the formation of microvoids, the absence of a plastic deformation process, and degradation at the fiber-matrix interface., INTRODUCTION Poly(butylene terephthalate) (PBT) is a semicrystalline thermoplastic polyester widely used as a matrix material in the production of short fiber reinforced thermoplastic (SFRTP) composites. This is because of its [...]

The efficiency of electroseparating the constituents of a polyvinyl chloride (PVC)-metal (aluminum or copper) granular mixture depends on the moisture content of the materials. Laboratory researches have been accomplished in order to determine the acceptable superficial humidity of the granules to be separated. The experimental study has been carried out on a roll-type laboratory separator with corona-electrostatic field. Ten samples of 50% PVC and 50% aluminum or copper, with the moisture content in the range 0 < W [is less than or equal to] 0.9%, have been identically processed. Several diagrams show the influence exerted by the humidity on PVC and metal recovery from the considered granular mixture. Efficient PVC - metal separations can be obtained for a moisture content of less than 0.3%. Experimental results are qualitatively discussed on the basis of the electrical charge of the PVC grain, the time constant of the discharge process, and the electric image force.

The purpose of this paper is to present theory and experiments on heat and moisture diffusion in magnetic tape packs. The theory includes anisotropy effects. The same fundamental mathematical theory is applied to heat and moisture diffusion. The tape packs have been submitted to a variety of thermal and hygroscopic conditions. By fitting experimental curves, a heat diffusivity coefficient of 1.8 [centered dot] [10.sup.-7] [m.sup.2]/s was obtained for the radial direction. Separate experiments showed that the heat diffusivity in the axial direction is about twice the value in the radial direction. For the radial moisture diffusivity coefficient, a literature value of 4 [centered dot] [10.sup.-13] [m.sup.2]/s is used. Fitting experimental curves then shows that the axial diffusion is about 300 to 500 times faster than the radial diffusion, which indicates that most of the moisture enters through the faces of the pack. Finally, it is shown that the experimental pack boundaries are not at a fixed temperature. Heat diffusion experiments in a stirred water bath best approximate the constant temperature requirement, and theoretical fits to those$experimental curves have been most satisfactory.