Analysis of Sugar Cane Production in Relation to Climate, Soil and Management

The yield of sugar cane is analyzed in relation to climate, soil and management. Detailed Information is obtained from the Waialua Sugar Company Inc. on Oahu, where approximately 4200 ha of irrigated sugar cane are grown under fully mechanized conditions. The field records date back to 1930, but a selected group of data for the period 1960-1970 has been used for statistical interpretation. Management variables Include month of harvest, crop cycle, age in months, nitrogen, potassium and phosphorus fertilization, amount of irrigation water applied and the number of days after the last round of irrigation until harvest. The climatic variables are rainfall during winter, rainfall during summer, rainfall one month before harvest; rainfall, maximum and minimum temperature and diurnal difference in temperature during the harvest month, average monthly evaporation and global radiation. The soils are mapped in detail and the yield data are grouped according to the major soil series on which sugar cane is grown in this plantation. Two soil series (Wahiawa and Lahalna) belong to the Order of the Oxisoils and cover almost 50% of the terrain, while another 40% is classified as Haplustolls (Ewa, Waialua, Kawaihapai, Pulehu, and Haleiwa). The remaining 10% of the area belongs to poorly drained Inceptlsols and Vertisols (Pearl Harbor and Kaena), The seasonal variation in climate with warm sunny summers and cool rainy winters is one of the determining factors in sugar production. Heavy rainstorms in winter show a negative effect on the production. Age of the crop is negatively correlated when the yield is expressed as Ton Sugar per Acre per Month. A significant drop in yield is observed in ratoon cropping. This decrease was more pronounced in the lowland soils. Sugar yield from the first plant crop is higher than the yield from the second plant crop. Since all other management practices and climatic factors are similar for both plant crops, this drop in yield must be considered as a genuine yield decline. During the 1930's the lowland areas produced more sugar than the fields located on chemically infertile Oxisols in the uplands. Increasing amounts of fertilizers since that time reduced the effect of the limiting fertility factor. The heavy machinery introduced since 1935 created poor physical conditions in the alluvial soils – impeded drainage, compaction and stickiness.- The result is that during the last decade the Oxisols produced significantly more sugar than the alluvial soils in spite of less favorable climatic conditions at higher elevation. The limiting factor appears to have changed from fertility to physical conditions. An analysis of variance test clearly demonstrated the significant difference in yield between these two soil groups. From this study it becomes clear that all three systems-climate, soil and management-play an Important role in the final yield figure. While it is not possible to estimate the yield satisfactorily with only one of these systems-the explained variation in yield varied from 18% to 34%- the combination of the three systems explained more than 70% of the yield variation. Almost 80% of the estimated yield data differed less than 5% from the actual yield. Because this study was carried out over a relatively large area and actual plantation records were used Instead of an experimental design, the unexplained variation is still considerable. However this study indicates that agricultural research designed to interpret actual field data should give equal importance to the three systems that control crop growth: Climate, soil and management

NMR Studies of Emulsions in Porous Media and Applications to Fischer-Tropsch Synthesis

As global reserves of conventional fossil fuels are dwindling, Fischer-Tropsch (FT) is a promising and greener method to convert natural gas into liquid fuels. However, it is highly complex and remains thus far poorly understood. The work presented in this thesis employs nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) to gain insight into and elucidate the multiphase behaviour and transport processes of Fischer-Tropsch Synthesis (FTS) reactants and products. In order to achieve this, the world’s first operando NMR compatible reactor was designed, commissioned and built to ultimately optimise the conversion of Gas-to-Liquids (GTL) through the FT process. A particular focus of this work lies on the application of a pulsed-field gradient (PFG) NMR emulsion detection technique to characterise hydrocarbon-in-water emulsions and study their droplet size distribution (DSD) inside porous media under operando conditions ($\geq$180 $\degree$ C and $\geq$36 bar). The initial study into droplet formation was done on $\theta$-Al2O3 pellets by relaxometry and PFG NMR measurements at ambient conditions, where dodecane and water were model compounds for FT products. The relaxation results indicated that water was the surface wetting phase, while dodecane was isolated from the pore surface. Spontaneous dodecane-in-water droplets formed, suggested by the restrictive diffusion behaviour for dodecane in the binary mixture. This trend was confirmed in Q-silica beads as well as in Ru-based FT catalyst pellets. Subsequently, the influence of (i) temperature, (ii) pore size, (iii) surfactant and (iv) surface modification on emulsion formation was investigated. Little impact of temperature and pore size was found for the ranges studied. However, a longer alcohol chain length lead to a small increase in droplet size. Furthermore, if the catalyst surface became hydrophobic with stearic acid, spontaneous emulsion formation did no longer occur. Studying FTS $\textit{in situ}$ can be very complex due to its high P and T. This thesis contains the first ever reported operando study of FT under real operating conditions. This work resulted in spatially-resolved MRI measurements of the diffusion and spatial mapping of product formation inside catalysts. These results can be used to validate numerical reactor simulations and optimise catalyst development. Finally, the phase behaviour of wax and water was studied post-FTS $\textit{in situ}$ in 1~wt$\%$~Ru/TiO2 catalysts at both 180 and 220~$\degree$ C. Emulsion formation was detected by slowly increasing the water partial pressure between 0.3~-~0.95. At \textit{P}/\textit{P}\textsubscript{0}~\leq~0.5, both water and wax diffused freely. However, at \textit{P}/\textit{P}\textsubscript{0}~\geq~0.8, capillary condensation of water inside the catalyst pores was reported. This resulted in the formation of a water-rich, surface-wetting layer, located in between the pore surface and the wax layer. The wax species were displaced and became isolated from the pore space, which was confirmed by the significant increase in both \textit{T}\textsubscript{1} and $\textit{D}$ values. For \textit{P}/\textit{P}\textsubscript{0}~\geq~0.9, wax-in-water emulsions spontaneously formed. This was concluded from the sudden drop in the diffusion behaviour for wax.Department of Chemical Engineering and Biotechnology, Shel

Summary of the 3rd IAEA technicalmeeting on divertor concepts

This report summarizes the contributions presented at the 3rd IAEA technical meeting on divertor concepts, held in Vienna, Austria, 4–7 November 2019. The meeting brought together more than 70 experts from nuclear fusion research sites worldwide to discuss the different aspects that the divertor design and fusion machine operation involve, from ITER divertor developments to innovative technologies for future DEMO divertor. The main topics of the meeting were: divertor and confinement; radiative power exhaust; scrape-off layer (SOL) and divertor physics; steady state operation and transient heat loads; plasma facing components materials and heat exhaust for steady state operation; and divertors for DEMO and future power reactors

Safety of dried fruits of Synsepalum dulcificum as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on dried fruits of Synsepalum dulcificum as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is pitted and dried (by lyophilisation) fruits of S. dulcificum. The NF contains the glycoprotein miraculin (≤ 2.5%) which causes sour and acidic foods to taste sweet. The fruits have a documented history of consumption in Africa and products thereof can be found in different markets worldwide. Information on the production process and the composition of the NF is sufficient and does not raise safety concerns. The applicant proposes to use the NF as or in food supplements for the adult population, excluding pregnant and lactating women, at a maximum daily amount of 0.9 g. Taking into account these conditions of use, the Panel considers that the consumption of the NF is not nutritionally disadvantageous. The provided genotoxicity studies do not raise concerns for genotoxicity of the NF. The Panel concludes that the only dose tested in a 90-day oral toxicity study of 2,000 mg/kg body weight (bw) per day was not associated with adverse effects. By applying an uncertainty factor of 200, the Panel concludes that the NF is safe at an intake level of 10 mg/kg bw per day, corresponding to a maximum daily intake of 0.7 g of the NF for the target population, rather than 0.9 g/day as proposed by the applicant