Despite the growing interest in traditional cuisine, to the present author’s knowledge no linguistic analysis of Polish culinary recipes has been conducted so far. Even though numerous studies of recipes written in other languages, such as English, have been published, the structure and typology of early Polish recipes have, as yet, been ignored. The aim of the present paper is to investigate the earliest known Polish collection Compendium Ferculorum, and collate these fi ndings with what is known about this text type from other languages. Such an analysis will show whether the earliest Polish instructions, which appeared relatively late, i.e. in the 17th century, follow the pattern which is typical of the period or rather that of an earlier stage in the evolution of the recipe, as was the case with the earliest American recipes (Dylewski 2016).
The research was intended to develop a biocomposite as an alternative biodegradable material, for the production of, e.g., disposable utensils. The author’s tested thermoplastic maize starch, both without additives and with the addition of crumbled fl ax fi ber in the share of 10, 20 and 30 wt%. The plasticizer added was technical glycerin and the samples were produced by a single-screw extruder. The mechanical strength tests were performed, including the impact tensile test and three-point bending fl exural test. Afterwards, the samples were tested for biodegradability under anaerobic conditions. The methane fermentation process was carried in a laboratory bioreactor under thermophilic conditions with constant mixing of the batch. All samples proved to be highly susceptible to biodegradation during the experiment, regardless of the fl ax fi ber share. The biogas potential was about 600 ml·g-1, and the methane concentration in biogas ranged from 66.8 to 69.6%. It was found, that the biocomposites can be almost completely utilized in bioreactors during the biodegradation process. The energy recovery in the decomposition process with the generation of signifi cant amount of methane constitutes an additional benefi t.
2-phase composites are often used for high demanding parts that can undergo impact loads. However, most of the papers on dynamic loading concerns layered composites. In our opinion, the impact loads are not considered thoroughly enough. Good examples of 2-phase composites are: (1) a WC/Co cermet or (2) a monolithic ceramic Al2O3/ZrO2. The WC/Co cermet is often modelled as having ductile elasto-plastic Co matrix and ideally elastic WC grains. It is because of very high crushing resistivity of the WC.
In this paper, we present an extension to earlier elaborated models ([44]) with the assumption of ideal elasticity of the grains. The new and general numerical model for high-velocity impact of the 2-phase composites is proposed. The idea of this novelty relies on the introduction of crushability of grains in the composite and thermo-mechanical coupling. The model allows for description of the dynamic response both composite polycrystals made of: (1) 2 different purely elastic phases (e.g. Al2O3/ZrO2) or (2) one elastic phase and the second one plastic (e.g. cermet WC/Co), or (3) 2 elasto-plastic phases with different material properties and damage processes. In particular, the analysis was limited to the cases (2) and (3), i.e. we investigated the WC/Co polycrystal that impacted a rigid wall with the initial velocity equal to 50 m/s.
The following discussion concerns modelling of fracture in steel plates during an impact test, in which both target and striker are manufactured from the same material, high-strength high-hardness armour steel – Mars® 300. The test conditions (3 mm thick targets, projectiles with different nose shapes at impact velocity lower than 400 m/s) result in severely damaged components, which results in an analysis of stress states showing material failure. Numerical analyses are performed using two material models: the Johnson-Cook approach, as traditionally used in impact simulations, accounting for the effect of stress triaxiality, strain rate and temperature and for comparison, a simulation by means of the stress triaxiality and Lode angle parameter-dependent Hosford-Coulomb model, also incorporating the effect of the strain rate on a fracture initiation. The aim of the study is to analyse the mechanisms of penetration and perforation observed in the armour steel plates and validation of the modelling approaches.
As the dynamic behavior of the concrete is different from that under static load, this research focuses on the study of dynamic responses of concrete by simulating the split Hopkinson pressure bar (SHPB) test. Finite element code LS-DYNA is used for modeling the dynamic behaviors of concrete. Three continuous models are reviewed and the Holmquist-Johnson-Cook model (HJC) is introduced in detail. The HJC model which has been implemented in LS-DYNA is used to represent the concrete properties. The SHPB test model is established and a few stress waves are applied to the incident bar to simulate the dynamic concrete behaviors. The stress-strain curves are obtained. The stress distributions are analyzed. The crack initiation and propagation process are described. It is concluded that: the HJC model can modeling the entire process of the fracture initiation and fragmentation; the compressive of the concrete is significantly influenced by the strain rates.
The use of quantitative methods, including stochastic and exploratory techniques in environmental studies does not seem to be sufficient in practical aspects. There is no comprehensive analytical system dedicated to this issue, as well as research regarding this subject. The aim of this study is to present the Eco Data Miner system, its idea, construction and implementation possibility to the existing environmental information systems. The methodological emphasis was placed on the one-dimensional data quality assessment issue in terms of using the proposed QAAH1 method - using harmonic model and robust estimators beside the classical tests of outlier values with their iterative expansions. The results received demonstrate both the complementarity of proposed classical methods solution as well as the fact that they allow for extending the range of applications significantly. The practical usefulness is also highly significant due to the high effectiveness and numerical efficiency as well as simplicity of using this new tool.