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91.
92.
Positional‐species composition (PSC) of 1,2,3‐triacyl‐sn‐glycerols (TAG) from the arils of mature fruits of 13 species of Euonymus L. genus was established. The residues of six major fatty acids (FA), palmitic, stearic, hexadecenoic (H), octadecenoic (O), linoleic (L), and linolenic, were present in the TAG. PSC of TAG was determined by their partial lipase hydrolysis. By using hierarchical cluster and principal component analyses, it was definitely demonstrated that separate taxonomic units forming this genus were significantly distinguished as regards PSC of TAG. In particular, the Euonymus subgenus greatly exceeded the Kalonymus subgenus in both total content of L in TAG and in the rate of its incorporation into their mid‐position, while TAG of Kalonymus were marked by a prevalence of O‐TAG and sn‐2‐O isomers. Thus, these subgenera were significantly distinct in the rate of incorporation of O and L residues in the sn‐2 position of TAG molecules. Meanwhile, the TAG from the Euonymus section species were marked by an enhanced concentration of H and the incorporation of H in UUU TAG was much more active than in other TAG types. As for positional‐type composition of TAG, saturated FA were always virtually absent in the sn‐2 position of Euonymus aril TAG.  相似文献   
93.
The mechanics of granular media at low liquid saturation levels remain poorly understood. Macroscopic mechanical properties are affected by microscale forces and processes, such as capillary forces, inter-particle friction, liquid flows, and particle movements. An improved understanding of these microscale mechanisms is important for a range of industrial applications and natural phenomena (e.g. landslides). This study focuses on the transient evolution of the tensile stress of unsaturated granular media under extension. Experimental results suggest that the stress state of the material evolves even after cessation of sample extension. Moreover, we observe that the packing density strongly affects the efficiency of different processes that result in tensile stress relaxation. By comparing the observed relaxation time scales with published data, we conclude that tensile stress relaxation is governed by particle rearrangement and fluid redistribution. An increased packing density inhibits particle rearrangement and only leaves fluid redistribution as the major process that governs tensile stress relaxation.  相似文献   
94.
In this paper, the utilization of different chaotic systems as pseudo-random number generators (PRNGs) for velocity calculation in the PSO algorithm are proposed. Two chaos-based PRNGs are used alternately within one run of the PSO algorithm and dynamically switched over when a certain criterion is met. By using this unique technique, it is possible to improve the performance of PSO algorithm as it is demonstrated on different benchmark functions.  相似文献   
95.
The cleaning of filter cloths is necessary to avoid prolonged system downtime and strong fouling. Reliable cleaning concepts are central to the removal of residues from the complex surface of filter cloths. Particle residues, in particular, play a decisive role in the sufficiency of the cleaning performance. Consequently, enhanced particle‐removal cleaning concepts based on pulsatile jets for filter cloths have been developed. By varying the cleaning parameters, it has been demonstrated that increased pulse numbers and velocities improve the cleaning performance. Furthermore, this promising cleaning concept cleaned more effectively than conventional methods. The reduction in the amount of detergent needed is an ecological and economic advantage of pulsatile cleaning.  相似文献   
96.
Due to the growing stock of torrent control structures and decreasing investments, the protection level can be reduced in the long term. Therefore, the focus of the future investments has been shifted on efficiency improvement and maintenance of existing structures. The maintenance of the existing structures is necessary to ensure safety from natural hazards, which are increasing as a consequence of the climate change. Due to the increasing number of structures, there is a strong need to develop a good maintenance management for these infrastructure works. This study is based on data from the condition rating programme of the Austrian Service for Torrent and Avalanche Control. For the structures relevant in this work, 75,343 records were available. The data were examined for different construction type and construction materials. The reliability of the structures was determined by means of the Markov chain. The study describes a homogeneous Markov chain model formed by the data of the condition rating. The result of this study is a proposal for a time to failure (TTF) and a time to repair (TTR) for several construction types with different construction materials as well as the time-dependent use of construction materials in the sector of the Austrian torrent control infrastructure.  相似文献   
97.
Moškon  Miha  Komac  Roman  Zimic  Nikolaj  Mraz  Miha 《Neural computing & applications》2021,33(15):8923-8938
Neural Computing and Applications - Ever since its foundational years, synthetic biology has been focused on the implementation of biological computing structures. In the beginning, engineered...  相似文献   
98.
Flexible barriers are increasingly used for the protection from debris flow in mountainous terrain due to their low cost and environmental impact. However, the development of a numerical tool for the rational design of such structures is still a challenge. In this work, a hybrid computational framework is presented, using a total Lagrangian formulation of the finite element method to represent a flexible barrier. The actions exerted on the structure by a debris flow are obtained from simultaneous simulations of the flow of a fluid‐grain mixture, using two conveniently coupled solvers: the discrete element method governs the motion of the grains, while the free‐surface non‐Newtonian fluid phase is solved using the lattice Boltzmann method. Simulations on realistic geometries show the dependence of the momentum transfer on the barrier on the composition of the debris flow, challenging typical assumptions made during the design process today. In particular, we demonstrate that both grains and fluid contribute in a nonnegligible way to the momentum transfer. Moreover, we show how the flexibility of the barrier reduces its vulnerability to structural collapse, and how the stress is distributed on its fabric, highlighting potential weak points.  相似文献   
99.
Journal of Intelligent Manufacturing - Continuous casting is the most important route for the production of steel today. Due to the physical, mechanical, and chemical components involved in the...  相似文献   
100.
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