Knowledge of the engineering properties of seeds, grains, nuts, kernels, and fruits is vital in the design of planting, harvesting, and postharvesting machines. This study investigates moisture‐dependent geometrical, gravimetrical, frictional, rheological, and aerodynamical properties of arugula seed. The length, width, and thickness of the seed distributions were modeled by the Normal, Log‐normal, and Weibull probability density functions. In the moisture ranges of 4.68–20.50%, the major, intermediate, and minor seed dimensions increased from 2.01 to 2.35 mm, 1.60 to 1.98 mm, and 1.17 to 1.33 mm, respectively. The results indicated that Log‐normal distribution had the best performance in most cases. Values of 1,000‐seed mass, bulk density, particle density, and porosity ranged between 1.33 to 1.77 g, 703.07 to 644.37 kg m−3, 1,160 to 1,392 kg m−3, and 39.39 to 53.71% as in the above moisture ranges. The filling and emptying angles of repose increased from 29.21° to 34.78° and 37.95° to 39.75°, respectively, as the moisture content increased. Incremental trends were observed for terminal velocity in water and air and residual stress during relaxation tests. Decreasing trends were observed for drag coefficient, modulus of elasticity, maximum contact stress, toughness, hardness, rupture force, and reduced stress during relaxation tests.Practical ApplicationsArugula (Eruca vesicaria L. or Eruca sativa Mill L.) is a popular worldwide vegetable. Besides consuming its leaves as a vegetable, the oil extracted from its seeds has industrial uses. This study investigated properties of arugula seeds with varying moisture contents with a view to understand their relevance in mechanical processing and bulk handling. The results presented in the current work would contribute to designing the metering devices (distributors), sorters, separators, cleaners, transportation systems, conveyors, oil extractors, etc.

In the present study, barberries were poured into a topless cylinder with a diameter of 55 mm and were subjected to axial compression force up to 440 kg (4,314.926 N). Effects of duration of water exposure, loading rate, and number of layers were investigated on momentary juice mass, Stress–strain behavior, and stress‐relaxation behavior. Considering momentary porosity, the momentary juice mass, stress–strain, and stress‐relaxation behaviors of the berries were modeled by inverse tangent function, exponential function, and One‐term Maxwell model, respectively. The extraction yield of juice (EYJ), specific absorbed energy by berries (SAEB), and efficiency index of energy (EIE) were calculated, and their analysis of variance and optimization were performed. The results showed that the R2 of the exponential model for the Stress–Strain diagram, Maxwell model for relaxation behavior, and inverse tangent model for momentary juice mass variation were more than 0.975, 0.985, and 0.995, respectively. The effects of the three operating parameters on the stiffness factor of springs and damping factor of dashpot were significant at 5%. Furthermore, the effects of the three input variables on the juice point force, juice point energy, EYJ, SAEB, and EIE were significant at 1%. Practical Applications The first step in producing barberry products in accordance with international food standards is barberry juice extraction. In the current study, the axial pressure method, one of the conventional barberry juicing methods, was investigated. This method has more ability to control the quality of juice than other methods. Traditionally, fruits are soaked in water for several hours before barberry juicing. Also, in the loading stage, rigid plates are placed between the fruit layers. Duration of water exposure, loading rate, and the number of layers are the three major influential factors in the juicing process. The information obtained from this article can help optimize the barberry juicing process using existing axial pressure devices. Besides, the results can be used in the optimal design of the barberry‐juicing device.

In this work, polymerization of caprolactam (CL) was carried out in the presence of acrylonitrile butadiene rubber (NBR) during the reactive melt‐mixing process. During shear mixing, NBR particles swelled and dissolved in the molten CL, which led to separation and distribution of rubber particles to nanoscale in the dissolution stage. Then, in an internal mixer, supertough Polyamide 6 was prepared via melt polymerization of CL/NBR mixture, sodium caprolactam as a catalyst, and hexamethylene diisocyanate as an activator. The effects of various concentrations of catalyst and activator on the initiation time of the reaction were determined. Physical and mechanical properties of different formulations prepared via reactive melt blending were determined by tensile and impact measurements, differential scanning calorimetry, Fourier‐transform infrared spectroscopy, X‐ray scattering techniques, transmission electron microscopy, and dynamic mechanical thermal analysis. Experimental results showed that a recipe with 3% nitrile rubber in a CL/NBR mixture enhances the physical and mechanical properties the best, compared with other formulations. This condition led to the formation of NBR nanospheres during melt polymerization of Polyamide 6 as well. J. VINYL ADDIT. TECHNOL., 21:116–121, 2015. © 2014 Society of Plastics Engineers