600 research outputs found

    Sharply-Topped Alluvial Gravel Sheets in the Palaeogene Promina Basin (Dinarides, Croatia)

    Get PDF
    The upper part of the Promina Beds at their western extent is represented by two alluvial units: the Kunovac Beds and the Upper Alluvial Unit. The Kunovac Beds contain a high proportion of fine-grained sediments, and generally lacks debris flow deposits. The principal architectural components of the Kunovac Beds are (1) complex (multilateral, multi-storey) gravel-dominated sheets, which originated by the advance of mobile-channel belts, and were terminated by sudden abandonment, (2) smaller heterogeneous gravelly-sandy sheets, which originated in fluvial belts from a combination of sheet flows and channelized flows, (3) small isolated ribbons reflecting the filling of small channels, and (4) floodplain mudstones and sandstones. The basic style by which the Kunovac Beds, as well as the most part of the Promina alluvium were built up are the repeated advances and abandonments of the alluvial belts, and related stacking of coarse-grained sheets and floodplain deposits. The most important factors responsible for the dominance of this sheet-like geometry are high sediment supply and high aggradation and subsidence rates. Deposition of the Kunovac Beds occurred on alluvial plains, situated between the basin-margin proximal alluvium (including fans) and marginal-marine zone of the Promina Basin. The alluvial Promina Beds represent a transverse type of basin-fill pattern, whereas the deepest portion of the basin experienced longitudinal palaeotransport

    Exploiting shared structure in software verification conditions

    Get PDF
    Abstract. Despite many advances, todayā€™s software model checkers and extended static checkers still do not scale well to large code bases, when verifying properties that depend on complex interprocedural flow of data. An obvious approach to improve performance is to exploit software structure. Although a tremendous amount of work has been done on exploiting structure at various levels of granularity, the fine-grained shared structure among multiple verification conditions has been largely ignored. In this paper, we formalize the notion of shared structure among verification conditions, propose a novel and efficient approach to exploit this sharing, and provide experimental results that this approach can significantly improve the performance of verification, even on pathand context-sensitive and dataflow-intensive properties.

    Thermal relaxation of magnetic clusters in amorphous Hf_{57}Fe_{43} alloy

    Full text link
    The magnetization processes in binary magnetic/nonmagnetic amorphous alloy Hf_{57}Fe_{43} are investigated by the detailed measurements of magnetic hysteresis loops, temperature dependence of magnetization, relaxation of magnetization and magnetic ac susceptibility, including a nonlinear term. Blocking of magnetic moments at lower temperatures is accompanied with the slow relaxation of magnetization and magnetic hysteresis loops. All of the observed properties are explained with the superparamagnetic behaviour of the single domain magnetic clusters inside the nonmagnetic host, their blocking by the anisotropy barriers and thermal fluctuation over the barriers accompanied by relaxation of magnetization. From magnetic viscosity analysis based on thermal relaxation over the anisotropy barriers it is found out that magnetic clusters occupy the characteristic volume from 25 up to 200 nm3 . The validity of the superparamagnetic model of Hf_{57}Fe_{43} is based on the concentration of iron in the Hf_{100-x}Fe_{43} system that is just below the threshold for the long range magnetic ordering. This work throws more light on magnetic behaviour of other amorphous alloys, too

    Prevention of thermal degradation of red currant juice anthocyanins by phenolic compounds addition

    Get PDF
    The aim of this study was investigation of prevention of thermal degradation of the red currant juice anthocyanins by addition of different phenolic compounds (catechol, 4-methyl catechol, catechin, chlorogenic acid and gallic acid). Phenolic compounds were added in 50:1 and 100:1 copigment:pigment molar ratio. Red currant juice samples were heated at 30, 50, 70 and 90 Ā°C for 1 hour. Thermal degradation of anthocyanins was investigated through determination of anthocyanin content and calculation of the reaction rate constant, half-life of degradation, activation energy and anthocyanin retention. Anthocyanin content ranged from 34.32 mg/100 mL to 47.97 mg/100 mL in a red currant juice, depending on temperature. When phenolic compounds were added anthocyanin content ranged from 34.94 mg/100 mL to 50.41 mg/100 mL, depending on both temperature and added phenolic compounds. In all cases when phenolic compound were added, anthocyanin content, half-lives of degradation increased and the reaction rate constants decreased. The thermal degradation of anthocyanins was lower when phenolic compounds were added due to copigmentation effect. With increase of temperature copigmentation effect was less pronounced. The most contributing phenolic compounds on anthocyanin stability at 30 Ā°C was gallic acid, at 50 Ā°C and 70 Ā°C catechin, and at 90 Ā°C 4-methyl catechol. Concentration of phenolic compounds also had influence on investigated parameters

    Orthodontic-Prosthodontic Rehabilitation: a Case Report

    Get PDF
    A 25 year-old female came to the Department of Prosthodontics, complaining of problems with masticatory function, described as pain in both temporomandibular joints during mastication and dissatified with esthetics in the upper jaw. After a thorough clinical escaminations, diagnostic casts and X-ray analysis it was determined that the patent had oligodontium of 10 teeth (14, 15, 17, 18, 24, 25, 28, 38, 44, 48), discoloration of incisors caused by hypomaturated enamel (amelogenesis imperfecta), disproportion of the front teeth (in completely defined microdontia), Angle class II/1 (deep overbite) and compression of the front teeth. The case history showed that the problems were of a congenital nature apart from the frontal compression, caused by inadequate orthodontic therapy at a younger age. Despite numerous congenital abnormalities, the patient had no systemic disorders. In consultation with an orthodontist, the patient commenced orthodontic therapy with a fixed orthodontic appliance in the upper jaw for placing the teeth in the right position for fabrication of a semicircular bridge. After 6 months of orthodontic therapy, a fixed prosthodontic appliance 600321 123006 (upper jaw) was made of metal ceramic. The aim of the therapy was to replace missing teeth, protect existing teeth with hypomaturated enamel and readjust occlusal height. With the new intermaxillary relations and teeth contour esthetic and functional concordance was achieved. After therapy the patient had no pain in the temporomandibular joints

    Orthodontic-Prosthodontic Rehabilitation: a Case Report

    Get PDF
    A 25 year-old female came to the Department of Prosthodontics, complaining of problems with masticatory function, described as pain in both temporomandibular joints during mastication and dissatified with esthetics in the upper jaw. After a thorough clinical escaminations, diagnostic casts and X-ray analysis it was determined that the patent had oligodontium of 10 teeth (14, 15, 17, 18, 24, 25, 28, 38, 44, 48), discoloration of incisors caused by hypomaturated enamel (amelogenesis imperfecta), disproportion of the front teeth (in completely defined microdontia), Angle class II/1 (deep overbite) and compression of the front teeth. The case history showed that the problems were of a congenital nature apart from the frontal compression, caused by inadequate orthodontic therapy at a younger age. Despite numerous congenital abnormalities, the patient had no systemic disorders. In consultation with an orthodontist, the patient commenced orthodontic therapy with a fixed orthodontic appliance in the upper jaw for placing the teeth in the right position for fabrication of a semicircular bridge. After 6 months of orthodontic therapy, a fixed prosthodontic appliance 600321 123006 (upper jaw) was made of metal ceramic. The aim of the therapy was to replace missing teeth, protect existing teeth with hypomaturated enamel and readjust occlusal height. With the new intermaxillary relations and teeth contour esthetic and functional concordance was achieved. After therapy the patient had no pain in the temporomandibular joints

    Estimation of Wear Resistance in Acid Solution of Dental Ceramics by Neural Network

    Get PDF
    It is known that exposure to acid causes damage to the glass surface. The aim of this study was to examine wear resistance, measuring the mass change of dental ceramics after contact with 10-3 mol dm-3 HCl at temperature of 50Ā°C. Four samples of dental ceramics were analyzed: feldspatic ceramic, hydrothermal ceramic, glass ceramic for staining and glass ceramic for layering. The mass concentrations of eluted Na+, K+ and Ca2+ were determined by ion chromatography (IC) and mass concentrations of Si4+ and Al3+ by UV/VIS spectrometry. Measurements were conducted after 1, 2, 3, 6 and 12 months of emersion. For the subject issue, using experimental data, the feedforward backpropagation neural network for estimation of wear resistance of dental ceramics was modelled. The results of 1, 2 and 12 months of emersion were used for the training 13-20-5 model of neural network. Comparison of experimental data and data obtained by estimation (results of 3 and 6 month intervals) of neural network shows that the applied network model provided a very good prediction of wear behavior of dental ceramics with high correlation coefficient (R) and low sum of squared error (SSE) between measurement and estimated output values

    Physico-chemical Properties of Corn Extrudates Enriched with Tomato Powder and Ascorbic Acid

    Get PDF
    The aim of this research was to investigate the influence of the addition of tomato powder (TP) to corn grits at levels 4, 6 or 8 % and the addition of ascorbic acid (AA) at levels 0.5 and 1 %, on total polyphenol content (PF), and antioxidant activity of the extrudates. The hardness and the expansion ratio of the extruded products were also tested. Mathematical models that describe the influence of additives on the mentioned properties were also determined. Extrusion was performed at two temperature regimes: 135/170/170 Ā°C and 100/150/150 Ā°C. Lower temperature regime led to increased hardness and the expansion of extrudates. The addition of tomato and AA led to decreased hardness and the expansion at both temperature regimes. The addition of tomato increased PF and AA compared with pure corn extrudates. Greater degradation of PF and AA was at lower temperature regime. High correlation between PF and AA was demonstrated at both extrusion temperatures

    Fluktuacije faze supravodljivog uređenja u osnovnom stanju kao preduvjet jakih kritičnih fluktuacija u visokotemperaturnim supravodičima

    Get PDF
    We analyse the reversible magnetisation and heat capacity of YBa2Cu3O7āˆ’Ī“ in the ā€œvortex liquidā€ state and find that both properties are reasonably well described by the 3D XY critical-fluctuation model. The free-energy density in the ā€œvortex liquidā€ state has a particularly simple form over a wide range of fields (H) and temperatures (T). This leads us to a picture in which the presence of critical fluctuations in high-Tc superconductors is directly linked to the remarkably small number of overlapping Cooper pairs at T=0 and H=0 rather than low dimensionality or high temperatures.Analiziramo reverzibilnu magnetizaciju i toplinski kapacitet YBa2Cu3O7āˆ’Ī“ u stanju ā€œtekućine vrtlogaā€, i nalazimo da su oba svojstva razumno dobro opisana 3D XY modelom kritičnih fluktuacija. U velikom području polja (H) i temperatura (T), gustoća slobodne energije u stanju ā€œtekućine vrtlogaā€ ima osobito jednostavan oblik. To nas vodi do slike u kojoj je prisustvo kritičnih fluktuacija u visokotemperaturnim supravodičima neposredno povezano s vrlo malim brojem prekrivajućih Cooperovih parova pri T =0i H = 0, prije nego s niskom dimenzionalnoŔću ili visokim temperaturama
    • ā€¦
    corecore