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Agricultural stakeholders can effectively manage the risks and opportunities arising from climate change and variability by enhancing climate services in agriculture. Key to understanding and addressing the climate challenge is the provision and the use of climate information to aid decision-makers and policy-makers. Climate services are now integral to the United Nations Framework Convention on Climate Change, the Intergovernmental Panel on Climate Change’s Assessment Reports, governments’ national adaptation plans, funding bodies, and a growing number of sectors and industries worldwide. The article provides our personal perspective, experience, and views on the important and timely issue of managing better the risks and opportunities to the agriculture sector and community that are arising from changes in climate. We describe a framework to help drive action to tackle the climate challenge comprising enhanced knowledge and information products, efficient information delivery and use, and assured policy and institutional support, in an iterative loop.

Polyethylene glycol (PEG) and glycerol were tested as melt assistants to enhance the melt processability of poly(acrylonitrile-co-1-vinyl imidazole) (co-PAN). The effects of the melt assistants on the molecular mobility of co-PAN were investigated through molecular dynamics (MD) simulations, and the specific volume changes with temperature were analyzed to evaluate the efficiency of the melt assistants theoretically. The MD results demonstrated that both PEG and glycerol increase the specific volume of co-PAN compared to pristine co-PAN. However, the effects of PEG in terms of increasing the specific volume and mobility of co-PAN were superior to those of glycerol. These findings were verified by variations in the shear viscosity of the co-PAN. Spinnability was improved significantly for co-PAN/PEG, and a more uniform co-PAN melt-spun filament could be obtained compared to co-PAN/glycerol. Thus, PEG200 is the best melt assistant for co-PAN, and 15% (w/w) is the optimal content for the melt-spinning of co-PAN.

Microwave curing technology, which has seen increased commercialization recently due to its ability to cut the curing time and ensure high quality, requires an understanding of the curing characteristics of composite materials of varying thickness. Therefore, this study aimed to perform cure monitoring to evaluate the effects of variations in thickness on the quality of microwave curing. For this study, a fiber Bragg grating sensor was used to measure temperature changes in specimens during the curing cycle for cure monitoring which is generally used for optimization of the curing cycle, then, the time taken for temperature increase and overshoot of the specimen, and the times at which the specimen thickness varied, were quantitatively evaluated. Testing confirmed that microwave curing reduced the curing time in the sections in which the temperature rose, also, the specimen thickness caused overshoot of up to approximately 40 &deg, C at the side, which can affect the curing quality of the composite materials. Furthermore, voids were observed on the side of all specimens. The results indicated that, in order to improve the quality of microwave curing of composite materials, the curing cycle should be optimized by considering the characteristics of the microwave curing equipment.

Single step synthesis of dimethyl ether (DME) from syngas on the bifunctional catalysts of CuO–ZnO–Al2O3 deposited on Al2O3-modified H-ferrierite was investigated to elucidate effects of Al2O3 modification of H-ferrierite in terms of CO conversion and DME yield. The enhanced catalytic activity was observed on the bifunctional catalysts at an optimum content of Al2O3 on H-ferrierite around 2.5–5 wt%. It is attributed to a higher dispersion of Al2O3 on H-ferrierite with an enhanced interaction of copper particles with Al2O3 modified H-ferrierite with a lower aggregation property by adjusting acidic sites and by increasing the dispersion of copper particles. The main role of Al2O3 on H-ferrierite is found to reduce strong acidic sites by depositing on the sites selectively, which resulted in showing a lower formation of byproducts. Both of copper surface area and amount of acidic sites are well correlated with an intrinsic activity (turn-over frequency; TOF), which revealed a structure-insensitive reaction character of a single-step synthesis of DME. The measurements of the dispersion of Al2O3 and copper particles with the number of acidic sites concomitantly were employed to verify the effects of Al2O3 modification of H-ferrierite though X-ray photoelectron spectroscopy, temperature-programmed methods and surface morphology characterizations.

The adsorption of charged dendrigraft (arborescent) copolymers of different generations (G1, G2) and side chain molecular weights (Mn ≈ 5000 or 30,000) on silica surfaces in water, was monitored by the quartz crystal microbalance dissipation (QCM-D) technique. The topology of the adsorbed copolymers on mica was also investigated by AFM measurements. The PS-P2VP [polystyrene-graft-poly(2-vinylpyridine)] copolymers readily interact with a silica or mica surface and form a thin layer in acidic water (pH 2) due to the positively charged P2VP shell branches. The adsorbed arborescent PS-P2VP films expanded and collapsed reversibly in water upon cycling between low and high pH values, respectively. As the generation number increased, the density of copolymer molecules adsorbed onto the surface decreased due to stronger intermolecular electrostatic repulsions. The adsorption density also decreased significantly for copolymers with longer P2VP chains due to their more expanded conformation on the surface.

Formation of porous films from poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) using the breath figures (BF) method was investigated by evaporating solutions in chloroform in humid air and examining film structure using optical and scanning electron microscopy (SEM). BF films were successfully fabricated from PHB (Mw = 486,000 g/mol) and displayed hexagonal arrays of pores, which varied in diameter (D = 7–2 μm) with solution concentrations (0.5–2.00%). SEM of fractured films also showed subsurface closed nano-pores (D = 500–700 nm). BF films cast from PHBV (5% HV) formed arrays with smaller pores and apparent surface defects. Differential scanning calorimetry showed that porous PHB and PHBV films produced using the BF method were more crystalline than nonporous solvent cast films of PHB and PHBV. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

Poly(ethylene terephthalate) (PET) nanocomposites with a newly synthesized organomica (C16BIMD-Mica) were obtained by using the in situ interlayer polycondensation of ethylene glycol with dimethylterephthalic acid. The PET hybrids were melt-spun to produce monofilaments with various organoclay contents and draw ratios. The thermomechanical properties and morphologies of the PET hybrid fibers were determined using differential scanning calorimetry, thermogravimetric analysis, wide angle X-ray diffraction, electron microscopy (SEM and TEM), and a universal tensile machine. The XRD analyses and TEM micrographs showed that the levels of exfoliation and intercalation could be controlled by varying the clay content. The thermomechanical properties of the PET hybrid fibers were found to be better than those of pure PET fibers. POLYM. ENG. SCI., 47:1820–1826, 2007. © 2007 Society of Plastics Engineers