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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