Influence of Variety,Moisture Content,Kernel Size and Applied Current Frequency on the Electric Properties of Wheat Grain

The work aimed at determination of electric properties of wheat grain in dependence on its variety, moisture, geometrical features of kernels and applied current frequency. Wheat grain of 4 Polish winter varieties: Korweta, Juma, Mikon and Kobra from harvest 2001 were used as the material for study. Grain was sized into 3 fractions: (1) > 2,8mm, (2) 2,5–2,8mm, and (3) 2,2–2,5mm. Basic geometrical features were determined for not sorted grain (control sample) and its three fractions by the use of digital image analysis. Electric properties of grain (at 11% and 15% moisture content) have been performed with the Hewlett Packard 4263B meter. Measurements of impedance, resistance, admittance, conductance, as well as equivalent parallel capacitance and equivalent series capacitance were made. Obtained results were subjected to statistical analysis with the use of Statistica? programme. Changes in electric properties of grain significantly depended on all of studied factors. Most of all significant correlations appeared between geometrical features and studied electric properties of grain of 15% moisture. Statistical analysis of the results proved significant linear correlations between electric properties of kernels and their length, perimeter and circularity coefficient R_C2 at higher measurement frequencies.     

The compression specificity of plant tissue

The aim of this study was to determine the compression characteristics of nonhomogeneous plant materials with a complex morphological structure (beetroots, celery roots, and potato tubers), to compare the analyzed samples with the compression characteristics of reference materials (homogeneous isotropic structural materials: steel coil spring and vulcanized rubber), and to determine the influence of the compression rate on stress in compressed samples. Structural materials and plant materials clearly differed in compression characteristics. Excluding the short initial compression phase, the compression curves for the steel coil spring and vulcanized rubber were straight parallel lines, and the higher the crosshead speed, the higher the lines' location in the diagram. In tests conducted on plant materials, the rate of changes in compression force increased throughout the experiment with an increase in crosshead speed. The greatest variations in compression force resulting from differences in crosshead speed were observed in potato samples. The apparent retardation times determined in the developed rheological model ranged from 0.079 s for the steel coil spring to 6.863 s for potatoes.     

Linear correlation between pH value of stimulated beef and electrical current intensity

The aim of the present study was to determine mathematical relationships between pH changes in beef 24 h post-slaughter and changes in the intensity of electrical current flowing through bull and heifer carcasses during high-voltage electrical stimulation. The electrical stimulation was applied 40 min postmortem for 120 s. The pH values of m. longissimus thoracis et lumborum were analyzed in the function of electrical current intensity changes and its change during electrical stimulation. Mathematical linear correlations of the y = ax ± b type were demonstrated between pH values at 2, 6, and 24 h postmortem and the initial (I_i) and ultimate (I_u) electrical current intensity values, the difference between them and the initial pH values determined before electrical stimulation. High multiple correlation coefficients (R² = 0.416, α ≤ 0.001) between I_u and pH values 24 h post-slaughter enabled concluding that there is a possibility to predict a pH value of stimulated carcass with high accuracy, and thus also beef quality, based merely on the ultimate electrical current intensity values.     

Crowding as an Agronomic Factor Determining the Development of Plants and the Productivity of Linseed (Linum usitatissimum L.)

ABSTRACT

Nine sowing densities of linseed were compared in a two-year experiment. Self-regulation of the density of a linseed stand resulted in a differentiated branching of the plants. The number of capsules on a linseed shoot, as well as seeds in the capsule, and the number of seeds from the shoot were highly varied from year to year, and there is even a stronger differentiation in the weight of 1000 seeds. Linear relationships were noted between the mass of seeds from the linseed plant and the number of capsules. The yield of linseed was affected by both factors. An increasing sowing rate reduced the seed yield from the shoot and the plant. At lower seeding rates, the lateral shoots contributed in the seeds yield of the plant to a higher degree compared to the main ones.     

A review of application of amine-terminated dendritic materials in textile engineering

Over the last decade, dendritic structures including hyperbranched polymers, dendrigrafts, dendrons, and dendrimers due to their distinct structural design such as highly branched structure and a large number of reactive end groups have received considerable attention. Among various kind of dendrimer, particularly amine-terminated dendritic materials like polyamidoamine (PAMAM), polypropylene imine (PPI), and polyethylene imine (PEI) have been introduced as the potential candidates in a wide range of areas, particularly in the field of textiles engineering. Hence, this review provides an introduction of amine-terminated dendritic polymers and new potential applications of them in textiles engineering such as improvement of dyeability, salt-free dyeability, antimicrobial activity, long-lasting fragrant fabric, anti-ultraviolet property, drug delivery through fabric, flame retardancy, and wastewater treatment. Regarding the complex synthesis of dendrimers which makes them expensive products, application of amine-terminated hyperbranched polymers provides affordable dendritic polymers to create novel features.     

Influence of the degree of fusariosis on technological traits of wheat grain

The paper aims to enlarge the current knowledge about the dependence of technological traits of wheat grain on its degree of infestation (DI) with fusariosis. Samples of grain of four wheat cultivars were obtained from naturally grown crops (control) and from crops inoculated with Fusarium culmorum from which three degrees of kernel infestation were selected. Samples were determined for thousand kernels weight (TKW), total protein, starch and wet gluten (WG) contents, Hagberg falling number (HFN) and sedimentation value (SV). Content of protein and wet gluten showed higher values for moderately infested kernels (up to 15 and 25%, respectively, when compared to control grain) than for kernels lightly or heavily infested. All the remaining traits had values lower than that for control grain and showed a decrease with increasing DI. Decrease for the heaviest infestation was on average: 8, 29, 31 and 34% for starch, TKW, HFN and SV, respectively.     

Deformation of Cotton Weft-Knitted Fabric Subjected to Tensile Loads

The main goal of paper presented is to introduce the SolidWorks environment to model the complex structure of knitted fabric. The geometrical model according to Leaf and Glaskin consists of some paths of unequivocal shape. The problem is described using the physical model and the set of mathematical equations. The structure is next discretized by means of finite element net and used to investigate the biaxial tensile elastic properties of cotton plain knitted fabrics. The obtained theoretical results are verified with a good convergence by means of tensile tests of knitted fabrics.     

An approach to modeling the rheological properties of food materials

The aim of this study was to develop a mathematical model describing the rheological properties of food materials, including the elastic modulus, consistency index, flow index and flow limit, that are not dependent on the tests (creep and compression stress relaxation) used to establish those values. A rheological model was designed as a parallel combination of spring, viscous and plastic elements. The model was verified logically and empirically based on the results of creep tests and compression stress relaxation tests performed on 10 × 10 × 10 mm cubes cut out from roasted turkey breast muscles. An analysis of the model’s susceptibility to variations in rheological properties indicates that the model is sensitive to changes in the values of the elastic modulus, flow limit and flow index, but it is less susceptible to changes in the consistency index. The model generates similar values of the rheological properties of the studied materials regardless of whether they had been determined based on the results of the creep test or the compression stress relaxation test.