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131.
132.
The use of geosynthetics for construction of windmills on spread foundation. The spread foundation is most favourable for the construction of that larger and higher performance windmills regarding the economic criteria. The ground improvement is most proper for such spread foundations on soft soils with high settlement potential by using the base course installation (reinforced and unreinforced). Additional reinforcement elements like geosynthetic can be installed for the further increase of the bearing capacity, from which a more favourable distribution of load impact on the underground, stress peaks will be diminished and the resulting settlement will be more uniformly. For the analysis of the bearing capacity and stability‐increasing characteristics of geosynthetic reinforced base course under spread foundation of windmill in low load‐carrying soil, a numerical investigation with the program system PLAXIS 2d, version 8.2, was performed, whereby both the separate contribution of the filling soil as well as the reinforcing element was determined. It could be proven that the use of geosynthetics in reinforced base course entails a significant increase of safety as well as a tilting reduction.  相似文献   
133.
The main application fields of the fast neutrons are accelerator-driven subcritical systems (ADS) and fusion–fission (hybrid) reactor systems for fission energy production. Thorium (Th) and uranium (U) are nuclear fuels in these reactor systems. Lead (Pb), bismuth (Bi) and tungsten (W) are the target nuclei in the ADS reactor systems. The technical design of ADS and hybrid reactor systems require much effort and data. The Hartree–Fock (H–F) method with an effective interaction with Skyrme forces is widely used for studying the properties of nuclei such as binding energy, root mean square (RMS) charge radii, mass radii, neutron density, proton density, electromagnetic multipole moments, etc. In this study, by using H–F method with interaction Skyrme RMS charge radii, RMS mass radii, neutron density and proton density were calculated for the 232Th, 238U, 207Pb, 209Bi and 184W isotopes. The calculation results of charge radii were compared with experimental data. Obtained RMS mass radii, neutron density and proton density results were discussed for ADS and hybrid reactor systems.  相似文献   
134.
The influences of polymerization temperature, initiator and monomer concentrations, ionic strength of the aqueous phase, as well as ethylene glycol dimethacrylate (EGDM) co-monomer, on the kinetics of the emulsifier-free emulsion polymerization of methyl methacrylate (MMA) and on the properties of the resulting poly(methyl methacrylate) (PMMA) lattices were studied. The polymerizations were carried out using potassium persulfate (KPS) as the initiator. Monodisperse PMMA lattices with particle diameters varying between 0.14–0.37 μm and polymer molecular weights of the order 0.4 × 106 to 1.2 × 106 g/mol were prepared. The initial rate of polymerization increases with increasing temperature, KPS-MMA mole ratio, EGDM content, or with decreasing ionic strength of the aqueous phase. It was shown that the bead size can be limited by reducing the monomer concentration or by using the cross-linking agent EGDM. The ionic strength of the aqueous phase has a dominant effect on final particle diameter and polymer molecular weight. The uniformity of the latex particles increases as the temperature increases or as the initiator concentration decreases. The experimental results can be reasonably interpreted by the homogeneous nucleation mechanism of the emulsifier-free emulsion polymerization of MMA. © 1996 John Wiley & Sons, Inc.  相似文献   
135.
HTRs use a high performance particulate TRISO fuel with ceramic multi-layer coatings due to the high burn up capability and very neutronic performance. TRISO fuel because of capable of high burn up and very neutronic performance is conducted in a D-T fusion driven hybrid reactor. In this study, TRISO fuels particles are imbedded body-centered cubic (BCC) in a graphite matrix with a volume fraction of 68%. The neutronic effect of TRISO coated LWR spent fuel in the fuel rod used hybrid reactor on the fuel performance has been investigated for Flibe, Flinabe and Li20Sn80 coolants. The reactor operation time with the different first neutron wall loads is 24 months. Neutron transport calculations are evaluated by using XSDRNPM/SCALE 5 codes with 238 group cross section library. The effect of TRISO coated LWR spent fuel in the fuel rod used hybrid reactor on tritium breeding (TBR), energy multiplication (M), fissile fuel breeding, average burn up values are comparatively investigated. It is shown that the high burn up can be achieved with TRISO fuel in the hybrid reactor.  相似文献   
136.
The knowledge of the electrical properties of the materials to be processed or measured is important in the design of the equipment. Dielectric properties determine the behavior of the materials, when subjected to high frequency or microwave fields in dielectric heating processes or cooking. This article is a review of the measurement techniques of the dielectrical properties of food materials. This study also includes the classification of electrical properties and their importance in food processing.  相似文献   
137.
The effects of microwave and infrared drying on the quality of carrot and garlic were studied and compared with the effects of conventional hot air (tray drier for carrot and fluid bed drier for garlic) drying. The quality of carrot and garlic were evaluated by instrumental and sensory analysis. Rehydration, moisture content, water activity, particle density, bulk density, porosity and colour values were obtained for microwave, infrared and hot-air dried vegetables. In addition, total moisture content versus time was represented by drying rate curves of carrot and garlic samples. Finally, free moisture content versus drying rate were compared for the three different drying methods.  相似文献   
138.
We report controllable and enhanced hydrogen release kinetics at reduced temperatures in ammonia borane (AB) catalyzed by Zn-MOF-74. AB is loaded into the unsaturated Zn-metal coordinated one-dimensional hexagonal open nanopores of MOF-74 (ABMOF) via solution infiltration. The ABMOF system provides clean hydrogen by suppressing the release of detrimental volatile byproducts such as ammonia, borazine and diborane. These byproducts prevent the direct use of AB as a hydrogen source for polymer electrolyte membrane fuel cell applications. The H2 release temperature, kinetics, and byproduct generation are dependent on the amount of AB loading. We show that nanoconfinement of AB and its interaction with the active Zn-metal centers in MOF are important in promoting efficient and clean hydrogen generation.  相似文献   
139.
140.
The highly challenging hexaploid wheat (Triticum aestivum) genome is becoming ever more accessible due to the continued development of multiple reference genomes, a factor which aids in the plight to better understand variation in important traits. Although the process of variant calling is relatively straightforward, selection of the best combination of the computational tools for read alignment and variant calling stages of the analysis and efficient filtering of the false variant calls are not always easy tasks. Previous studies have analyzed the impact of methods on the quality metrics in diploid organisms. Given that variant identification in wheat largely relies on accurate mining of exome data, there is a critical need to better understand how different methods affect the analysis of whole exome sequencing (WES) data in polyploid species. This study aims to address this by performing whole exome sequencing of 48 wheat cultivars and assessing the performance of various variant calling pipelines at their suggested settings. The results show that all the pipelines require filtering to eliminate false-positive calls. The high consensus among the reference SNPs called by the best-performing pipelines suggests that filtering provides accurate and reproducible results. This study also provides detailed comparisons for high sensitivity and precision at individual and population levels for the raw and filtered SNP calls.  相似文献   
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