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This work describes the flexural behavior of biocomposites composed of a polyurethane matrix derived from castor oil plants and coir fibers. A statistical design is performed to identify the effects of fiber alkaline treatment and aging on the flexural modulus and strength of the composites. Physical tests and failure analyses are carried out to better assess their mechanical performance. A second experiment at 100% relative humidity is performed on treated fiber composites to compare with those obtained by immersion in water. The flexural modulus of the composites is not significantly affected by the fiber alkali treatment, while the strength is reduced by 35.17% when treated fibers are considered. Increasing the exposure time of composites under both aging conditions progressively reduces their flexural properties. The aging process of biocomposites in an environment with 100% relative humidity takes twice as long to reduce to the same flexural properties as those aged in water. Highlights * Composites made with treated fibers showed higher apparent density and lower porosity. * Water aging reduces flexural modulus and strength of biobased coir composites. * The bending properties are strongly dominated by the properties of biobased polymer. * 100% relative humidity takes twice as long to reduce to the flexural properties as those aged in water. * Untreated coir fibers achieve superior bending properties under moisture aging. KEYWORDS aging process, alkaline treatment, biobased polyurethane, coir fiber, flexural properties, 1 | INTRODUCTION In recent years, the increase in nondegradable waste accumulated in landfills, mainly polymeric materials derived from petroleum, has generated considerable environmental problems. (1) For this reason, the [...]

Byline: U. Sirin and M. Okuroglu Keywords: calf stable, natural ventilation, underground piped natural ventilation, temperature, relative humidity INTRODUCTION It is likely with the creation of enough ventilation in animal [...]

We have studied the evaporation of water droplets containing silica nanoparticles of various hydrophobicities deposited on a super-hydrophobic substrate. Evaporation induces particle accumulation at the droplet surface and results in the formation of a crust that buckles during further shrinkage. For droplets containing hydrophilic particles, a bowl-shaped crust was observed. For droplets containing hydrophobic particles, the crust develops a multi-buckled shape that could be completely suppressed by increasing the relative humidity. The varied buckling behavior of droplets may be attributed to the different mechanical properties of the gelled layer where particle hydrophobicity plays a role. Our work highlights the important role of particle hydrophobicity and relative humidity in the final crust morphology, thus shedding light on crust shape control and material design via the droplet evaporation approach. Key words: colloidal droplet, evaporation, sol-gel transition, buckling. Nous etudions l'evaporation de gouttelettes d'eau contenant des nanoparticules de silice de differentes hydrophobies, deposees sur un substrat super-hydrophobe. L'evaporation induit une accumulation de particules a la surface de la gouttelette, resultant en la formation d'une croute qui se deforme sous un retrecissement additionnel. Pour des gouttelettes contenant des particules hydrophiles, nous observons alors une croute a deformations concaves. Pour des gouttelettes contenant des particules hydrophobes, la croute developpe des deformations multiples, qui peuvent etre completement effacees en augmentant l'humidite relative. Le comportement varie des gouttelettes peut etre attribue a differentes proprietes de la couche exterieure, ou l'hydrophobicite des particules joue un role. Notre travail souligne le role important de l'hydrophobicite et de l'humidite relative dans la morphologie finale de la croute, jetant une lumiere sur le controle de la forme et du design du materiau via l'approche d'evaporation de la gouttelette. Mots-cles: gouttelettes colloidales, evaporation, transition sol-gel, deformation., 1. Introduction The evaporation of a droplet, though ostensibly a simple phenomenon in everyday life, involves tremendously complex physical, chemical, and mechanical processes, such as evaporation-driven flow [1], self-assembly [2], [...]

Pre-harvest soybean seeds in the field are susceptible to high temperature and humidity (HTH) stress, leading to pre-harvest seed deterioration, which will result in a reduction in grain quality, yield, and seed vigor. To understand the gene expression involved in seed deterioration response under HTH stress, in this study, we conducted an RNA-Seq analysis using two previously screened soybean cultivars with contrasting seed deterioration resistance. HTH stress induced 1081 and 357 differentially expressed genes (DEGs) in the sensitive cultivar Ningzhen No. 1 and resistant cultivar Xiangdou No. 3, respectively. The majority of DEGs in the resistant cultivar were up-regulated, while down-regulated DEGs were predominant in the sensitive cultivar. KEGG pathway analysis revealed that metabolic pathways, biosynthesis of secondary metabolites, and protein processing in endoplasmic reticulum were the predominant pathways in both cultivars during seed deterioration under HTH stress. The genes involved in photosynthesis, carbohydrate metabolism, lipid metabolism, and heat shock proteins pathways might contribute to the different response to seed deterioration under HTH treatment in the two soybean cultivars. Our study extends the knowledge of gene expression in soybean seed under HTH stress and further provides insight into the molecular mechanism of seed deterioration as well as new strategies for breeding soybean with improved seed deterioration resistance. Key words: soybean, high temperature and humidity, RNA-Seq, pre-harvest seed deterioration. Avant la recolte, les graines de soja au champ sont sensibles a un stress cause par une temperature et une humidite elevees (HTH), ce qui peut entrainer une deterioration des grains en pre-recolte, laquelle diminue la qualite des grains, le rendement et la vigueur des graines. Pour comprendre les profils d'expression genique associes a cette deterioration en reponse au stress HTH, les auteurs ont realise une etude RNA-Seq sur deux cultivars prealablement identifies comme presentant une resistance contrastee a cette deterioration. Le stress HTH a permis d'identifier, respectivement, 1081 et 357 genes a expression differentielle (DEG) chez le cultivar sensible Ningzhen No. 1 et le cultivar resistant Xiangdou No. 3. La majorite des DEG chez le cultivar resistant etaient exprimes a la hausse, tandis que les genes moins fortement exprimes etaient predominants chez le cultivar sensible. Une analyse des sentiers KEGG a revele que les 'sentiers metaboliques', la 'biosynthese des metabolites secondaires' et la 'maturation des proteines dans le reticulum endoplasmique' etaient les sentiers predominants touches lors de la deterioration des graines soumis a un stress HTH. Les genes impliques dans la photosynthese, le metabolisme des hydrates de carbone, le metabolisme des lipides et les proteines de choc thermique pourraient contribuer a la reponse differente observee entre les deux cultivars soumis a un traitement de stress HTH. Cette etude accroit les connaissances sur l'expression genique chez les graines de soja en reponse au stress HTH et fournit un eclairage sur le mecanisme moleculaire de la deterioration des graines ainsi que sur de nouvelles strategies pour selectionner des sojas dotes d'une meilleure resistance a la deterioration des graines. [Traduit par la Redaction] Mots-cles : soja, temperature et humidite elevees, RNA-Seq, deterioration des graines en pre-recolte., Introduction Soybean seeds provide major sources of oil and protein globally for human consumption and animal feed (Saha and Sultana 2008). Seed quality is determined by its composition of protein, [...]

ABSTRACT To realize the promise of improved predictions of hazardous weather such as flash floods, wind storms, fog, and poor air quality from high-resolution mesoscale models, the forecast models must [...]

Byline: A. Cayli and A.N. Baytorun Key words: Greenhouses, Vapor pressure deficit, VPD, Greenhouse heating, Greenhouse climate INTRODUCTION Greenhouses are a controlled-environment agricultural structure, where high quality and high yield [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2010.07.004 Byline: J. Korecko (a), V. Jirka (a), B. Sourek (a)(b), J. Cerveny (a)(c) Keywords: Rasters made of glass; Greenhouse; Solar architecture; Fresnel lens; Mathematical simulation Abstract: Since the eighties of the 20th century, various types of linear glass rasters for architectural usage have been developed in the Czech Republic made by the continuous melting technology. The development was focused on two main groups of rasters - active rasters with linear Fresnel lenses in fixed installation and with movable photo-thermal and/or photo-thermal/photo-voltaic absorbers. The second group are passive rasters based on total reflection of rays on an optical prism. During the last years we have been working on their standardization, exact measuring of their optical and thermal-technical characteristics and on creation of a final product that could be applied in solar architecture. With the project supported by the Ministry of Environment of the Czech Republic we were able to build an experimental greenhouse using these active and passive optical glass rasters. The project followed the growing number of technical objectives. The concept of the greenhouse consisted of interdependence construction - structural design of the greenhouse with its technological equipment securing the required temperature and humidity conditions in the interior of the greenhouse. This article aims to show the merits of the proposed scheme and presents the results of the mathematical model in the TRNSYS environment through which we could predict the future energy balance carried out similar works, thus optimizing the investment and operating costs. In this article description of various technology applications for passive and active utilization of solar radiation is presented, as well as some results of short-term and long-term experiments, including evaluation of 1-year operation of the greenhouse from the energy and interior temperature viewpoints. A comparison of the calculated energy flows in the greenhouse to real measured values, for verification of the installed model is also involved. Author Affiliation: (a) ENKI, o.p.s., Dukelska 145, 379 01 Trebon, Czech Republic (b) Czech Technical University of Prague, Technicka 4, 166 07 Prague, Czech Republic (c) Institute of Physical Biology, Zamek 136, 373 33 Nove Hrady, Czech Republic Article History: Received 17 April 2009; Revised 1 June 2010; Accepted 3 July 2010 Article Note: (miscellaneous) Associate Editor - I. Farkas

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2010.03.002 Byline: Prasad G. Thoppil (a), Patrick J. Hogan (b) Keywords: Persian Gulf; Shamal wind; Heat flux; Circulation; Numerical model Abstract: The results from a[approximately equal to]1km resolution HYbrid Coordinate Ocean Model (HYCOM), forced by 1/2[degrees] Navy Operational Global Atmospheric Prediction System (NOGAPS) atmospheric data, were used in order to study the dynamic response of the Persian Gulf to wintertime shamal forcing. Shamal winds are strong northwesterly winds that occur in the Persian Gulf area behind southeast moving cold fronts. The period from 20 November to 5 December 2004 included a well defined shamal event that lasted 4-5 days. In addition to strong winds (16ms.sup.-1) the winter shamal also brought cold dry air (T.sub.a =20[degrees]C, q.sub.a =10gkg.sup.-1) which led to a net heat loss in excess of 1000Wm.sup.-2 by increasing the latent heat flux. This resulted in SST cooling of up to 10[degrees]C most notably in the northern and shallower shelf regions. A sensitivity experiment with a constant specific humidity of q.sub.a =15gkg.sup.-1 confirmed that about 38% of net heat loss was due to the air-sea humidity differences. The time integral of SST cooling closely followed the air-sea heat loss, indicating an approximate one-dimensional vertical heat balance. It was found that the shamal induced convective vertical mixing provided a direct mechanism for the erosion of stratification and deepening of the mixed layer by 30m. The strong wind not only strengthened the circulation in the entire Persian Gulf but also established a northwestward flowing Iranian Coastal Current (ICC, 25-30cms.sup.-1) from the Strait of Hormuz to about 52[degrees]E, where it veered offshore. The strongest negative sea level of 25-40cm was generated in the northernmost portion of the Gulf while the wind setup against the coast of the United Arab Emirates established a positive sea level of 15-30cm. The transport through the Strait of Hormuz at 56.2[degrees]E indicated an enhanced outflow of 0.25 Sv (Sva 10.sup.6 m.sup.3 s.sup.-1) during 24 November followed by an equivalent inflow on the next day. Author Affiliation: (a) Technology Solutions Group, QinetiQ North America, Stennis Space Center, MS 39529, USA (b) Naval Research Laboratory, Open Ocean Processes and Prediction Section, Stennis Space Center, MS 39529, USA Article History: Received 26 October 2009; Revised 22 February 2010; Accepted 4 March 2010

The potential of an elliptical-orbit Flower Constellation of Millimeter-Wave Radiometers (FLORAD) for humidity profile and precipitating cloud observations is analyzed and discussed. The FLORAD mission scientific requirements are aimed at the retrieval of hydrological properties of the troposphere, specifically water vapor, cloud liquid content, rainfall, and snowfall profiles. This analysis is built on the results already obtained in previous works and is specifically devoted to evaluate the possibility of (i) deploying an incremental configuration of a Flower constellation of six minisatellites, optimized to provide the maximum revisit time over the Mediterranean area or, more generally, midlatitudes (between [+ or -] 35[degrees] and [+ or -] 65[degrees]); and (ii) evaluating in a quantitative way the accuracy of a one-dimensional variational data assimilation (1D-Var) Bayesian retrieval scheme to derive hydrometeor profiles at quasi-global scale using an optimized set of millimeter-wave frequencies. The obtained results show that a revisit time over the Mediterranean area (latitude 25[degrees] 45', longitude -10 [degrees] 35'[degrees]) of less than about 1 and 0.5 h can be obtained with four satellites and six satellites in Flower elliptical orbits, respectively. The accuracy of the retrieved hydrometeor profiles over land and sea for a winter and summer season at several latitudes shows the beneficial performance from using a combination of channels at 89, 118, 183, and 229 GHz. A lack of lower frequencies, such as those below 50 GHz, reduces the sounding capability for cloud lower layers, but the temperature and humidity retrievals provide a useful hydrometeor profile constraint. The FLORAD mission is fully consistent with the Global Precipitation Mission (GPM) scope and may significantly increase its space-time coverage. The concept of an incremental Flower constellation can ensure the flexibility to deploy a spaceborne system that achieves increasing coverage through separate launches of member spacecrafts. The choice of millimeter-wave frequencies provides the advantage of designing compact radiometers that comply well with the current technology of minisatellites (overall weight less than 500 kg). The overall budget of the FLORAD small mission might become appealing as an optimal compromise between retrieval performances and system complexity. DOI: 10.1175/2010JAMC2329.1

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1600-0706.2009.18124.x Byline: Gotz Froeschke, Rainer Harf, Simone Sommer, Sonja Matthee Abstract: As a consequence of environmental change, it is expected that shifts in temperature and precipitation patterns will influence parasite communities and their hosts with unpredictable impact. Parasites play a vital role in ecosystems but there is only limited quantitative data which describe the effects of environmental parameters under natural conditions. We investigated the influence of rainfall, relative humidity and temperature on the prevalence, abundance and infection intensity of nematodes in southern Africa by studying the gastro-intestinal helminth community of the striped mouse Rhabdomys pumilio. Along a precipitation gradient from the Cape of South Africa to northern Namibia we trapped 470 mice over a geographical distance of about 1400 km. Faecal egg counts of 439 sampled individuals and dissections of 161 gastro-intestinal tracts revealed 15 different helminth species. The most abundant nematode species harboured in 62.6% of all infected mice were the oxyurid Syphacia obvelata followed jointly by two species (Heligmonina spira and Neoheligmonella capensis) of the subfamily Nippostrongylinae (43.7%). We found a significant positive correlation between mean annual precipitation (rainfall and relative humidity) and nematode infestation rates of animals and a negative correlation with temperature. In addition, we found associations between precipitation and different qualitative measurements of parasite burden (mean nematode species richness, mean number of nematode worms and infection intensity per individual host). The similarity in nematode species composition decreased with distance between all study sites. Our study indicates for the first time an association between climatic variables and parasite prevalence and abundance along a continuous natural climatic gradient in a small mammal. These results might be incorporated in the development of models which can predict possible threats for the balance of ecosystems and shifts in infestation patterns due to global changes. Author Affiliation: (1)Evolutionary Genetics, Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Stra[beta]e 17, DE-10315 Berlin, Germany (2)Animal Ecology and Conservation, Univ. of Hamburg, Martin-Luther-King-Platz 3, DE-20146 Hamburg, Germany (3)Dept. Conservation Ecology and Entomology, Private Bag X1, Univ. of Stellenbosch, Matieland, 7602, South Africa Article History: Paper manuscript accepted 9 October 2009 Article note: S. Sommer, Evolutionary Genetics, Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Stra[beta]e 17, DE-10315 Berlin, Germany. E-mail: sommer@izw-berlin.de

This study analyzes the occurrence of the visibility (Vis) versus precipitation rates (PR) for rain and versus relative humidity (RH) from surface observations that were collected during the Fog Remote Sensing and Modeling (FRAM) field project, which was conducted near Toronto, Ontario, Canada, during the winter of 2005/06 and in Lunenburg, Nova Scotia, during the summers of 2006 and 2007. The main observations used in the analysis were PR and Vis for rain episodes from the Vaisala, Inc., FD12P present-weather sensor and RH and temperature from the Campbell Scientific Instruments, Inc., HMP45 sensor. The PR is compared with those from a total precipitation sensor to check the accuracy of the FD12P measurements. Vis parameterizations related to precipitation type have been previously studied by many other researchers and showed large variability in Vis (up to 1 order of magnitude) for a fixed PR. The results from the work presented here suggest that 1) significant differences exist among the various parameterizations of Vis (deterministic approach) and 2) statistical relationships obtained using fits applied to percentiles (probabilistic approach) can be a feasible alternative for model applications. Comparisons of previous parameterizations with the new Vis relationships suggest that simulated Vis values based on probabilistic approaches could be used in extreme-weather applications. DOI: 10.1175/2009JAMC1927.1

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2009.07.032 Byline: Tetsuya Tokano Keywords: Titan; Atmospheres, structure; Meteorology Abstract: The detection of large hydrocarbon seas/lakes near the poles by the Cassini spacecraft raises the question as to whether and how polar seas affect the meteorology on Titan. The polar meteorology and methane hydrological cycle in the presence of seas are investigated by a three-dimensional atmospheric general circulation model coupled to a one-dimensional sea energy balance model considering the observed sea/lake geography. The sea composition has a large control on the seasonal evolution of seas, temperature and wind system in the polar region, particularly in the north where large seas are located. The surface of ethane-rich seas, which do not evaporate methane, undergo a large seasonal temperature variation and the sea surface is often warmer than the surrounding land surface. Land breeze in summer towards the seas causes a moisture convergence over the seas, which leads to enhanced summer precipitation in the sea area. On the other hand, methane-rich seas evaporate some methane and are therefore colder than the surroundings. This causes a sea breeze across the north pole in summer, which blows away the moisture from the polar region, so precipitation becomes scarce in the north polar region. The breeze can become stronger than the tidal wind. Sea evaporation peaks in winter, when the temperature and average methane mixing ratio in the planetary boundary layer become lowest. The sea level predominantly rises in summer by precipitation and retreats in winter by evaporation. The meteorology in the south polar region is less sensitive to the composition of the lakes because of the paucity and smallness of southern lakes. Lake-effect precipitation can occur either by moisture convergence by the breeze or humidity enhancement over the seas, but is more characteristic of warm seasons than of cold seasons. Author Affiliation: Institut fur Geophysik und Meteorologie, Universitat zu Koln, Albertus-Magnus-Platz, 50923 Koln, Germany Article History: Received 11 November 2008; Revised 16 July 2009; Accepted 22 July 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2009.06.018 Byline: D. Kolokotsa, A. Psomas, E. Karapidakis Keywords: Urban heat island; Urban discomfort; Heat stress; Coastal area Abstract: The aim of the present paper is to analyze the results of the urban heat island research for a coastal densely built small Mediterranean town namely Hania, Crete, Greece. The specific research targets to verify the existence, the intensity, the size and the form of the urban heat island phenomenon in the specific region as well as to understand its correlation with the local weather conditions. Nine urban and three rural meteorological stations are used for this study. Temperature and relative humidity measurements are collected from May 26, 2007 until October 24, 2007. In parallel, meteorological data including wind speed and direction, barometric pressure, sunlight and precipitation for the specific region are collected and elaborated for cross-correlation with the appearance of the urban heat island (UHI) phenomenon. During summer period, where the temperature is high, the UHI takes its maximum intensity, of about 8[degrees]C. Also, the form of the UHI is strongly influenced from the wind speed and direction. The northern winds expand the UHI front, while the western winds contribute to the UHI reduction. Finally the Discomfort Index (DI) is calculated for the 2007 summer period to indicate the outdoor living conditions. Author Affiliation: Technological Educational Institute of Crete, Department of Natural Resources and Environment, 3 Romanou Str., 73133 Hania, Crete, Greece Article History: Received 31 March 2009; Revised 24 June 2009; Accepted 25 June 2009 Article Note: (miscellaneous) Communicated by: Associate Editor Matheos Santamouris

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2009.06.015 Byline: Nadine Reefmann (a)(b), Beat Wechsler (a), Lorenz Gygax (a) Abstract: The assessment of emotional states in animals, particularly positive ones, remains a scientific challenge. We investigated differences in behavioural and physiological measures recorded in sheep, Ovis orientalis aries, during situations likely to coincide with negative, intermediate and positive emotional valence. Reactions of 15 sheep were observed during separation from group members (negative valence), standing in the feeding area (intermediate valence) and being voluntarily groomed by a familiar human (positive valence). Several ear postures, relative eye aperture, cardiorespiration and body surface humidity and temperature were recorded continuously for up to 4min in each experimental situation. Data were analysed using linear mixed-effects models, and correlations were calculated between ethophysiological measurements. Groomed sheep showed few ear posture changes, low proportions of forward ear postures, low relative eye aperture and a low variance in body surface humidity. The values of most of these measures increased linearly towards standing in the feeding area and further towards separation from group members. Conversely, groomed sheep showed high proportions of axial ear postures, long mean interheartbeat intervals and high heart rate variability, with values declining linearly towards the negative situation. In addition, behavioural and cardiac measurements correlated moderately to strongly. In conclusion, emotional valence in sheep could be differentiated by both behavioural and physiological measures. Based on our data, it may be possible to replace some physiological measures with observations of ear postures. The findings provide valuable insights for assessing both negative and positive emotion in animals, which can help to promote positive experiences in captive housing conditions. Author Affiliation: (a) Centre for Proper Housing of Ruminants and Pigs, Federal Veterinary Office, Agroscope Reckenholz-Tanikon Research Station ART, Tanikon, Switzerland (b) Department of Behavioural Biology, University of Munster, Germany Article History: Received 21 December 2008; Revised 6 February 2009; Accepted 9 June 2009 Article Note: (miscellaneous) MS. number: 08-00819R

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2008.12.006 Byline: Thosapon Katejanekarn (a), Surapong Chirarattananon (b), S. Kumar (a) Keywords: Liquid desiccant; Dehumidification; Ventilation; Solar regeneration; Hot and humid; Experimental study Abstract: A solar-regenerated liquid desiccant ventilation pre-conditioning system has been installed and experiments were carried out for a period of nine months covering rainy, cold, and hot seasons in a hot and humid climate (Thailand). A heat exchanger was used to cool the dehumidified air instead of typical evaporative cooling to maintain the dryness of the air. The use of solar energy at the regeneration process and cooling water from a cooling tower makes the system more passive. The evaporation rate at the regeneration process was always greater than the moisture removal rate at the dehumidification process indicating that the concentration of the desiccant in the system would not decrease and so the performance would not drop during continuous operation. The system could reduce the temperature of the delivered air by about 1.2[degrees]C while the humidity ratio was reduced by 0.0042kg.sub.w/kg.sub.da equivalent to 11.1% relative humidity reduction. The experimental results were also compared with models in literature. Author Affiliation: (a) School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand (b) School of Energy and Materials, King Mongkut's University of Technology Thonburi, 91 Pracha-Uthit Rd., Bangmod, Thungkru, Bangkok 10140, Thailand Article History: Received 8 February 2008; Revised 8 July 2008; Accepted 14 December 2008 Article Note: (miscellaneous) Communicated by: Associate editor P. Gandhidasan

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2008.01.016 Byline: J.D. Chittenden (a)(b), V. Chevrier (a), L.A. Roe (c), K. Bryson (a), R. Pilgrim (a), D.W.G. Sears (a)(b) Keywords: Mars; Ices; Mars; surface; Mars; atmosphere Abstract: We have studied the effect of wind velocity on the sublimation rate of pure water ice under martian conditions. Measurements were made for wind velocities ranging from 0.7 to 11.4 mas.sup.-1, a typical range observed by the meteorological instruments on the surface of Mars, and at -15[degrees]C a value typical of the daily high temperature for most of the year at the Pathfinder landing site. At this temperature, and for a low-humidity environment (relative humidity around 1%) sublimation rates increase following a linear trend of equation E.sub.S=0.68+0.025V (E.sub.S is the sublimation rate in mmah.sup.-1 and V is the wind speed in mas.sup.-1). In high relative humidity (30-35%) atmospheres, the effect of wind velocity is negligible, and the sublimation rate remains nearly constant at 0.33[+ or -]0.04 mmh.sup.-1. Pure forced convection theory did not provide a satisfying description of the data in terms of the range of values and their wind speed dependency. Therefore, a new semi-empirical expression for the sublimation rate that combines free and forced convection was developed using analogy with heat transfer models. Using this expression, sublimation rates of ice as a function of wind velocity for any temperature can be calculated. In general, temperature is more important that wind speed and atmospheric humidity in determining the rate of sublimation of ice on Mars. Author Affiliation: (a) W.M. Keck Laboratory for Space Simulation, Arkansas Center for Space and Planetary Science, MUSE 202, University of Arkansas, Fayetteville, AR 72701, USA (b) Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA (c) Department of Mechanical Engineering, University of Arkansas, Fayetteville, AR 72701, USA Article History: Received 19 April 2007; Revised 28 January 2008

Dewpoint temperature, the temperature at which water vapor in the air will condense into liquid, can be useful in estimating frost, fog, snow, dew, evapotranspiration, and other meteorological variables. The goal of this study was to use artificial neural networks (ANNs) to predict dewpoint temperature from 1 to 12 h ahead using prior weather data as inputs. This study explores using three-layer backpropagation ANNs and weather data combined for three years from 20 locations in Georgia, United States, to develop general models for dewpoint temperature prediction anywhere within Georgia. Specific objectives included the selection of the important weather-related inputs, the setting of ANN parameters, and the selection of the duration of prior input data. An iterative search found that, in addition to dewpoint temperature, important weather-related ANN inputs included relative humidity, solar radiation, air temperature, wind speed, and vapor pressure. Experiments also showed that the best models included 60 nodes in the ANN hidden layer, a [+ or -] 0.15 initial range for the ANN weights, a 0.35 ANN learning rate, and a duration of prior weather-related data used as inputs ranging from 6 to 30 h based on the lead time. The evaluation of the final models with weather data from 20 separate locations and for a different year showed that the l-, 4-, 8-, and 12-h predictions had mean absolute errors (MAEs) of 0.550[degrees], 1.234[degrees], 1.799[degrees], and 2.280[degrees]C, respectively. These final models predicted dewpoint temperature adequately using previously unseen weather data, including difficult freeze and heat stress extremes. These predictions are useful for decisions in agriculture because dewpoint temperature along with air temperature affects the intensity of freezes and heat waves, which can damage crops, equipment, and structures and can cause injury or death to animals and humans.

Crystals growing in confined spaces can generate stress and are a major cause of damage in porous materials. To investigate such deleterious processes, appropriate in situ techniques are required. This paper describes the use of X-ray diffractometry under controlled conditions of temperature and relative humidity (RH-XRD) for the direct observation of phase transition reactions in a porous substrate. An improved environmental chamber without temperature gradients is presented and applied to the investigation of phase transformations in the system [Na.sub.2]S[O.sub.4] + [H.sub.2]O. This salt is generally considered as particularly damaging and frequently used in accelerated weathering tests. It is demonstrated that RH-XRD can be successfully applied for the direct observation of several relevant phase transitions in glass frits used as porous substrates. The conversion of [Na.sub.2]S[O.sub.4](III) to [Na.sub.2]S[O.sub.4](V) and the hydration of [Na.sub.2]S[O.sub.4](V) both proceed fairly rapidly as true solid-state reactions without deliquescence of the educt phases. In contrast, crystallization from solution is kinetically hindered as there is a strong tendency of aqueous [Na.sub.2]S[O.sub.4] to form supersaturated solutions also in narrow pores. The important implications of this behavior of the salt are also briefly discussed in the paper.

A portable fiber-optic spectroscopic system (TRANSPEC) has been developed for nondestructive measurement of aged transformer insulating paper. Following successful measurement of degree of polymerization (DP) of a range of transformer-aged paper samples, the system has now been shown to separate the oil and paper information for measurement of DP in oil-wetted paper samples. In addition, the system has been shown to be capable of the prediction of both oil and water content of paper to a high accuracy, and is also capable of identifying and quantifying different water species. Spectroscopic measurements have been used together with gravimetric water adsorption measurements to investigate the kinetics of uptake of water vapour into paper from air in the case of nominally dry and oil-impregnated samples. Relationships between water adsorption parameters and properties of the paper insulation have also been investigated using measurements under controlled conditions. Index Terms--Humidity control, multivariate statistical analysis, oil insulation, paper insulation, power transformers, spectroscopy, weight measurement, water content

The investigation of kinetics and products of heterogeneous gas-surface reaction of anthracene and ozone as a function of ozone concentration and relative humidity (RH) is presented. The results have indicated that at atmospherically relevant ozone concentrations, the anthraquinone yield from the ozonolysis of anthracene under dry and high relative humidity conditions would be less than 1%.

This paper examines the dynamics of moist baroclinic modes, based on the idealized model of moist baroclinic instability devised by Emanuel et al. These authors found that the finite static stability along the downdraft prevents the explosive short-wave cyclogenesis of the zero stratification limit in the moist problem, and allows only moderate (order 2) changes in the growth rate and short-wave cutoff, even when the moist static stability vanishes. To understand the limiting role of the dry static stability, a constraint is derived in this paper that relates the updraft and downdraft structures. This constraint is based on continuity and implies that a bulk wavenumber (defined in the paper) scales as the relevant deformation radius in each region. Because neutral solutions are separable, the vertical structure can be encapsulated in terms of a single, equivalent wavenumber based on the downdraft width. This allows an interpretation of the results in terms of the equivalent dry mode. As the ratio between moist and dry static stability decreases, the downdraft width takes an increasingly larger fraction of the total wavelength. In the limit of moist neutrality all the wavelength is occupied by the downdraft, so that the short-wave cutoff is halved. The vertical phase tilt makes unstable solutions nonseparable, and prevents defining an equivalent wavenumber in that case. However, the constraint between the bulk wavenumbers still applies. As the moist stability is reduced, the updraft solution becomes more suboptimal; in the limit of moist neutrality, the updraft wavenumber equals the short-wave cutoff. This provides a bound to the maximum growth rate in the moist problem, which is in agreement with the results of Emanuel et al.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.socscimed.2005.04.049 Byline: P. Howden-Chapman (a), J. Crane (b), A. Matheson (a), H. Viggers (a), M. Cunningham (c), T. Blakely (d), D. O'Dea (a), C. Cunningham (e), A. Woodward (f), K. Saville-Smith (g), M. Baker (a), N. Waipara (h) Keywords: Housing; Health; Insulation; Randomised community trial; New Zealand Abstract: This paper describes the purpose and methods of a single-blinded, clustered and randomised trial of the health impacts of insulating existing houses. The key research question was whether this intervention increased the indoor temperature and lowered the relative humidity, energy consumption and mould growth in the houses, as well as improved the health and well-being of the occupants and thereby lowered their utilisation of health care. Households in which at least one person had symptoms of respiratory disease were recruited from seven predominantly low-income communities in New Zealand. These households were then randomised within communities to receive retrofitted insulation either during or after the study. Measures at baseline (2001) and follow-up (2002) included subjective measures of health, comfort and well-being and objective measures of house condition, temperature, relative humidity, mould (speciation and mass), endotoxin, beta glucans, house dust mite allergens, general practitioner and hospital visits, and energy or fuel usage. All measurements referred to the three coldest winter months, June, July and August. From the 1352 households that were initially recruited, baseline information was obtained from 1310 households and 4413 people. At follow-up, 3312 people and 1110 households remained, an 84% household retention rate and a 75% individual retention rate. Final outcome results will be reported in a subsequent paper. The study showed that large trials of complex environmental interventions can be conducted in a robust manner with high participation rates. Critical success factors are effective community involvement and an intervention that is valued by the participants. Author Affiliation: (a) He Kainga Oranga/Housing and Health Research Programme, Department of Public Health, Wellington School of Medicine and Health Sciences, University of Otago, P.O. Box 7343, Wellington South, New Zealand (b) Department of Medicine, Wellington School of Medicine and Health Sciences, University of Otago, New Zealand (c) Building Research Association of New Zealand Research Ltd, Wellington, New Zealand (d) Department of Public Health, Wellington School of Medicine and Health Sciences, University of Otago, New Zealand (e) Te Pumanawa Hauora, Department of Maori Studies, Massey University, Wellington, New Zealand (f) School of Population Health, University of Auckland, Auckland, New Zealand (g) Centre for Research Evaluation and Social Assessment Ltd, Wellington, New Zealand (h) Landcare Research Ltd., Auckland , New Zealand

This paper deals with the humidity uptake of some transformer liquids and its influence on the electrical breakdown. The investigations were performed under some selective outdoor conditions on different insulating liquids, e.g. mineral oil, ester and silicone used in HV transformers. The temperature was at 23 or 60 [degrees] C while the relative air humidity was varied between 20 and 90% to simulate climatic variation. The subject is important in a kind of HV transformer with an air breathing system and, even if in such transformer, where normally the air passes through a dehydrating apparatus with silica gel, a bad run of this apparatus can induce an accident. The scenario considered corresponds to such a defect in the breathing filter system, and thus when the insulating liquid in the transformer becomes in contact with humidity of atmospheric air. The work presented is in two parts. The first part relates the evolution of the breakdown voltage in terms of the insulating liquid humidity content. The second one describes the evolution of insulating liquid humidity content in terms of surrounding relative air humidity. This evolution is observed during 30 days and the results are discussed regarding the ac electric strength according to International Electrotechnical Commission (IEC) or Verband der Elektrotechnik Elektronik Informationstechnik e.V. (VDE) standards. A correlation between the surrounding relative air humidity, temperature and humidity uptake rate is derived.

The seasonal pattern of terpene content and emission by seven Mediterranean woody species was studied under field conditions. Emission rates were normalized at 30 degrees C and 1000 (mu)mol*m(super -2)*s(super -1) PFD (photosynthetic photon flux density). Bupleurum fruticosum, Pinus halepensis, and Cistus albidus stored large amounts of terpenes (0.01-1.77% [dry matter]) with maximum values in autumn and minimum values in spring. They emitted large amounts of terpenes (2-40 (mu)g*g DM(super -1*h(super -1), but with no clear seasonal trend except for Cistus albidus, which had maximum values in spring and minimum values in autumn. The nonstoring species Arbutus unedo, Erica arborea, Quercus coccifera and Quercus ilex also emitted large amounts of terpenes (0-40 (mu)g*g DM(super -1)*h(super -1) and also tended to present maximum emission rates in spring, although this trend was significant only for A. unedo. At the seasonal scale, emission rates did not follow changes in photosynthetic rates; instead, they mostly followed changes in temperature. From autumn to spring, the least volatile monoterpenes such as limonene were emitted at highest rates, whereas the most volatile monoterpenes such as (alpha)-pinene and (beta)-pinene were the most emitted in summer. The monoterpene emission rates represented a greater percentage of the photosynthetic carbon fixation in summer (from 0.51% in Arbutus unedo to 5.64% in Quercus coccifera) than in the rest of the seasons. All these seasonality trends must be considered when inventorying and modeling annual emission rates in Mediterranean ecosystems. Key words: (alpha)-pinene; limonene; Mediterranean woody species; photosynthetic rate; relative humidity; seasonality; temperature; terpene emission and storage; volatility.

The wear mechanisms of Metal-Evaporated magnetic tape-head interfaces have been investigated. A new apparatus was designed for the continuous observation of the tape surface when run in the still frame mode. The mild wear mechanism of the bumps on the ME tapes was proven using SEM and AFM. Four different types of wear debris were observed. Depending on wear debris formation, two types of spalling were emphasized. The effect of humidity in the range of 30-70 percent was also investigated. The wear mechanisms are discussed in terms of contact mechanics theory, coating failure modes, and humidity induced stiction theory.

The effect of dry and moist atmospheres on the microwave dielectric losses in highly porous alumina is analyzed. Data between those for sapphire and a fully densified alumina grade are compared. Findings show that the combination of humidity and porosity produces a very high dielectric loss which decreases sharply by the replacement of the moist atmosphere with dry gas. As shown by measurements between 1 mHz and 100 MHz, the source of the microwave loss is the high frequency tail of a low frequency process.

Abstract The influence of temperature, humidity, salinity, and the number of we-dry cycles in the atmospheric corrosion resistance of the AISI A-36 steel, painted with coatings based on epoxy and [...]

Infrared and microwave upper-tropospheric humidities (UTH) have been found to be largely similar. The minor differences between them arise from different data interpretations concerning clouds. As such a priori information from satellite retrievals should be as accurate as possible to prevent biases in the UTHs. The water vapor absorption/emission radiances garnered from Television Infrared Observation Satellite Operational Vertical Sounder/High-Resolution Infrared Sounder is found to be higher than those obtained from Special Sensor Microwave Water Vapor Profiler.

Hydrophobic compounds of polar aerosols exhibited the strongest impact of humidity on partitioning. Outdoor environmental chambers were used to determine the impact of humidity on the gas/partitioning of various kinds of semivolatile organic compounds within the organic strata of wood soot, diesel soot and secondary aerosols. Outdoor teflon film chambers showed experimental partitioning coefficients Kpr for various semivolatile organic compounds while theoretical Kp values were determined via activity coefficients and vapor pressures.

It is generally known that the humidity in the surrounding atmosphere influences wear processes in general. For fretting wear several authors examined the influence of humidity on the wear scar morphology and the composition of the wear debris. No agreement between the different results has been found, yet. In the present study, a distinction is made between running-in and steady-state fretting wear. Especially for the running-in stage, the influence of the humidity in ambient air on the friction and wear behavior and material transfer of steel surfaces subjected to contact vibrations has been investigated. The fretting experiments were conducted with a spherical against a fiat specimen under gross-slip regime. The fretting wear and accompanying material transfer between the contacting specimens quantitatively are measured with Thin Layer Activation method. It has been observed that high ambient humidity has a beneficial influence on the running-in fretting wear of steel surfaces. It has also been found that the results of several authors concerning the influence of humidity on the fretting wear of steel have to be treated with great care, as classical wear measuring techniques can give erroneous wear results.

The physiological effects of emersion of high or low level of humidity on Nephrops norvegicus were evaluated using seawater-soaked hessian with periodical flushes of seawater (high humidity, HH) or unprotected emersion (low humidity, LH). The quantitative measurements of haemolymph constituents such as ammonia, glucose and lactate as well as the assessment of respiratory conditions revealed that N. norvegicus can cope with emersion and that high humidity conditions have little effect on such adaptation to physiological stress.

Theoretical analysis shows that when water activity is larger than its threshold value and the dry radius of a particle is larger than 0.005 [[micro]meter], the deviation of curvature correction from unity can be accurately represented by the product of two terms, with one term strongly depending upon water activity and the other depending upon dry radius. Moreover, experimental data show that the water-activity-dependent term can be approximated by linear and one-third power functions of water activity. According to the approximation made to curvature correction, water activity is solved as analytical functions of relative humidity (RH). The analytically solved water activity is then used to compute particle equilibrium sizes using a known (observed) relationship between water activity and water uptake by unit mass of dry material. The accuracy of equilibrium sizes calculated with this method is checked with seven typical classes of aerosols. Results show that when RH [less than or equal to] 99.99%, the equilibrium radius computed with this method is accurate to within 3% (6%) if the dry radius of a particle is larger (smaller) than 0.02 [[micro]meter] and that when RH > 99.99%, equilibrium sizes can be estimated with an accuracy higher than 84%. Analytical approximation formulas are also derived for calculating critical equilibrium radii and critical supersaturation. The maximum relative errors of these formulas range from 3% to 15%.

Individual terms of the mass, heat, and moisture budget equations are evaluated for an atmospheric control volume in Colorado's Sinbad Basin using tethered balloon and surface energy budget data obtained during a 16.5-h period on 15-16 July 1988. The basin was chosen for its simple topography and arid climate, which simplified the evaluation of some of the budget terms. The paper documents the many assumptions that are required to evaluate the mass, heat, and moisture budget equations in confined terrain using small datasets. The nighttime outflow of air from the basin produced a compensatory mean sinking motion of 0.026 m [s.sup.-1] at the top of the basin control volume and brought warm air into the top of the basin atmosphere. In contrast to previous reports for well-drained valleys, a high rate of atmospheric cooling continued in this basin throughout the entire night. The cooling is attributed primarily to turbulent sensible heat flux divergence and, to a lesser extent, radiative flux divergence. Measured sensible heat fluxes on the basin floor were small, suggesting that downward turbulent sensible heat fluxes must be relatively stronger in the downslope flows that develop above the sidewalls. A general means of characterizing and comparing the energetics of basin and valley atmospheres is developed from the heat budget equation and is illustrated using data from other valleys and basins. An accompanying paper takes a complementary approach of evaluating the heat budget terms using a dynamic model.

Simultaneous measurements of atmospheric water vapor by Millimeter-wave Imaging Radiometer (MIR), Raman lidar and rawinsodes suggest that the MIR radiometric measurements are accurate to within plus minus 2 K and are capable for water vapor profiling. The retrieval process degrades the accuracy of relative humidity by 2%-5% per 1-K in the radiometric measurements.

A one-dimensional variational analysis technique is used to assimilate the total precipitable water (TPW) retrieved from Special Sensor Microwave/Imager (SSM/I) brightness temperature and specific humidity retrieved from Geostationary Operational Environmental Satellite (GOES) radiances. It is seen that the error reduction of specific humidity in the upper levels of the troposphere is due to the GOES retrievals, while in the lower levels it is due to SSM/I TPW.

Examination of diffusion, sorption and permeation of aldehydes and alcohols in three food packaging polymers as a function of humidity indicates that alcohol diffusion is lower at higher humidity and that an increase in humidity increases aldehyde diffusion. Both plasticizing effect of water and the interaction between aroma and water vapors explain the effects of humidity. The influence of humidity on barrier characteristics are higher for polymer films with lower crystallinity than for crystalline films.

Multiple internal reflection infrared spectroscopy of hydrogen-terminated Si(111) and (100) surfaces in air shows that surface oxidation is independent of surface roughness but requires moisture from air for the early oxidation phases. Surface Si-H bond oxidation on the Si surface is catalyzed by water but the bond is passive toward the oxygen molecule. Intermediate oxidation states exhibit characteristic spectral features.

A humidity-dependent birefringence in a poly(methyl methacrylate) waveguide has been observed. This dependence was determined by coupling both a transverse electric and a transverse magnetic mode into a waveguide and then measuring the relative phase at the output. With this method, values for Delta(sub TM) - Delta(sub TE) were found within the range of 5-90% relative humidity (RH). From the obtained data, Delta(n(sub TE) - n(sub TM))/Delta-RH as a function of humidity was calculated and plotted.