Rupture Energy Research Articles

Dynamic tests and mechanical model for water-saturated soft coal with various particle gradations

Particle gradations significantly affects the dynamic response of water-saturated soft coal. To obtain the dynamic response of soft coal to various particle gradations, static and dynamic mechanical properties of water-saturated soft coal with different particle gradations were tested and compared. During these processes, the enhancement coefficient of the dynamic mechanical parameters to the corresponding static mechanical parameters was set as an index to describe the effect of non-uniformity coefficient Cu and median diameter d50. The results demonstrate that both the static and dynamic mechanical parameters of the water-saturated soft coal were affected by particle gradations. The enhancement coefficient was affected by both the d50 and Cu, which was microscopically attributed to effect of the d50 and Cu on the average dynamic liquid bridge force and scale dynamic rupture energy among the particles based on the microstructure and dynamic fracture evolution processes. In addition, the dimensionless scale rupture energy model among the water-bearing particles varied with the d50 and Cu were further established and applied to discuss the effect mechanism of particle gradations on the dynamic response of water-saturated soft coal. On this basis, the support measures of roadways in coal seam with different particle gradations were further discussed.

Mathematical modeling for the prediction of some quality parameters of white rice based on the strength properties of samples using response surface methodology (RSM).

One of the major problems in predicting the quality properties of rice is that conducting experiments in the food industry can be highly expensive. The objective of this study was to predict some quality properties in varieties (Domsiah, Hashemi, Dorfak, and Kadus) via compression test at moisture levels 9 and 14% w.b. Based on historical data design, RSM was used to model and estimate of dependent variables (amylose (AC) and protein content (PC), gelatinization temperature, gel consistency GC), minimum (Min.V), final (FV), breakdown (BDV) and setback viscosity (SBV), peak time (PT) and pasting temperature (Pa.T)) through independent variables (the rate of force, deformation, rupture energy, tangent, and secant modulus). An ANOVA test showed that models were significant (p < 0.05). The most appropriate model for response variables prediction of AC and GC (Kadus 14%), PC (Domsiah 9%), Min.V, FV, and SBV (Dorfak 9%), BDV (Dorfak 14%), PT (Hashemi 14%), and Pa.T (Kadus 9%) was Rpred2 as 0.86, 0.85, 0.93, 0.955, 0.953, 0.94, 0.94, 0.86, and 0.91, respectively, with the most appropriate optimal values as 23.52%, 48, 10%, 164.95 RVU, 304.12 RVU, 162.66 RVU, 64.52 RVU, 6.09 min, and 92.45°C and desirability as 0.91, 0.95, 0.95, 0.80, 0.89, 0.83, 0.84, 0.89, and 0.96, respectively. The optimal values of the independent variables have a decreasing trend, and the optimal values of the response variables are proportional to the optimal conditions. The results indicated that the RSM could be quite useful in the optimization of the models developed for predicting the rice quality properties.

Investigation of suitability of marbles to standards with inequality expressions and statistical approach using some physical and mechanical properties

Marble, one of the metamorphic rock formation products, forms by undergoing different physical and chemical processes. The marble samples are tested under laboratory conditions to understand these processes. This study aims to find whether the Akcay region marble (Antalya) is compatible with national and international standards using some physical and mechanical properties. For this purpose, samples were subjected to some laboratory tests (real density, apparent density, total porosity, open porosity, breaking load, compressive strength, flexural strength, rupture energy). A number of statistical findings, linear equations, inequalities, and spatial distribution maps were obtained from the physical and mechanical data found at the end of the laboratory tests. The variables which were found to be statistically significantly correlated according to the results of the correlation analysis were analyzed using regression analysis; then their distributions were explained using linear equations. The spatial distribution maps of the variables reveal the part corresponding to the symbol color ranging between the light green and yellow and covering almost 70% of the area is compliant with both TurkStat and ASTM standards and this is proved using the inequalities.

Genome wide association mapping and candidate gene analysis for pod shatter resistance in Brassica juncea and its progenitor species.

We investigated phenotypic variations for pod shattering, pod length and number of seeds per pod in large germplasm collections of Brassica juncea (2n = 36; AABB) and its progenitor species, B. rapa (2n = 20; AA) and B. nigra (2n = 16; BB). Pod shatter resistance was measured as energy required for rupturing a mature dry pod, with a specially fabricated pendulum machine. Rupture energy (RE) ranged from 3.3 to 11.0mJ in B. juncea. MCP 633, NR 3350 and Albeli required maximum energy to shatter a pod. It ranged from 2.5 to 7.8mJ for B.rapa with an average of 5.5mJ. B. nigra possessed easy to rupture pods. Correlation analysis showed strong associations among these traits in B. juncea and B. rapa. Genome wide association studies were conducted with select sets of B. juncea and B. rapa germplasm lines. Significant and annotated associations predict the role of FRUITFULL, MANNASE7, and NAC secondary wall thickening promoting factor (NST2) in the genetic regulation of shatter resistance in B. juncea. NST2 and SHP1 appeared important for pod length and seeds per pod in B.rapa. Candidate gene based association mapping also confirmed the role of SHP1 and NST2 in regulating pod shattering and related pod traits in B.rapa and B.juncea. Footprints of selection were detected in SHP1, SHP2 (B. rapa, B. nigra and B. juncea), RPL (B. rapa) and NAC (B. juncea). Our results provide insights into the genetic architecture of three pod traits. The identified genes are relevant to improving and securing crop productivity of mustard crop.

Comparative analysis of moisture-dependent physical and mechanical properties of two varieties of African star apple (Chrysophyllum albidum) seeds relevant in engineering design

• Physical and mechanical properties of two varieties [big (udara) and small (nwannu)] of African star apple between 3.00% to 18.03% w.b were determined. • Geometric, gravimetric and frictional properties of the two varieties of African star apple increased with moisture, except angle of repose (frictional property). • Galvanized sheet surface showed the maximum coefficient of static. • Angle of repose was maximum for the udara variety • Mechanical properties decreased with increase in moisture content for the transverse, vertical and horizontal loading orientation. This study was conducted to investigate and compare the engineering properties of two varieties [big (Udara) and small (Nwannu)] of African star apple ( Chrysophyllum albidum ) seeds in Nigeria. The objectives were to determine the effect of moisture on some moisture-dependent physical and mechanical properties of the Udara and Nwannu seeds. The parameters considered were geometric (axial dimensions, mean diameters, surface area, sphericity, aspect ratio, and volume), gravimetric (bulk and true densities, 1,000 seed mass and porosity), frictional (angle of repose and static coefficient of friction) and mechanical (rupture force, rupture energy and deformation at rupture point) properties of the seeds in the moisture content range of 3.00–18.03% (w.b.). It was observed that moisture content have a significant effect on all the engineering properties studied at p ≤ 0.05. The result also revealed that the angle of repose of Udara seed was higher than Nwannu seed. The coefficient of static friction of the star apple seeds was greatest on the galvanized sheet surface, 0.526 for Nwannu seed and lowest on the aluminum surface, 0.210 for udara seed. The coefficient of static friction was higher on all surfaces for Nwannu seed than for Udara seed. The force required to rupture the seed, the rupture energy, and the deformation at rupture point of Udara and Nwannu seeds decreased with increase in moisture content for horizontal (x), transversal (y) and vertical (z) loading direction. The transverse position showed the highest values of rupture force for both, Udara and Nwannu seed, but higher in Udara than Nwannu variety. The lowest rupture force was obtained during horizontal loading for the two varieties but lower in Nwannu than Udara seed. Similar results were obtained for rupture energy. The vertical loading position indicated the highest deformation at rupture point for both, Udara and Nwannu seed, but higher in Udara than Nwannu, while, the lowest deformation at rupture point was recorded in transverse loading for the two varieties, but lower in Nwannu than Udara seed. Properties of kernels, grains, and seeds are essential in the development of equipment for transportation, handling, and processing.

Seismic Sequences of the 2017 Mainling Mw 6.5 Earthquake: Imaging the Seismogenic Fault by Aftershock Analysis

In the southeastern part of Tibet, an earthquake with a local magnitude of 6.9 occurred in the prefecture of Mainling on 18 November 2017. The mainshock and more than 900 aftershocks were recorded by a local seismic network comprising seven three-component seismic stations. In this study, both HypoDD location of aftershocks and focal mechanism inversion of moderate events were performed in order to accurately identify the pattern of active faults. The result reveals that the mainshock has a thrust source mechanism located at a depth of 14 km beneath the NE flank of the Namcha Barwa–Gyala Peri (NB-GP) massif. The aftershock sequences are caused mainly by two determined faults, one of which is the seismogenic fault stretching with a SE–NW trend parallel to the GP ridge and with a high NE-oriented dipping angle, and the other is activated by the mainshock and displays features of a SSE-NNW trend and SW-dipping, inferring the adjustment of stress in the focal area. The source parameters of the mainshock and the selected aftershocks show the reverse property of the seismogenic fault and its adjunct fault, thus inferring the backlash and uplift of the NB-GP massif, especially GP, for adjusting the uneven extrusion from the eastern Himalayan syntaxis to the adjacent Lhasa block. Furthermore, it is deduced that the rupture energy of the mainshock and aftershocks was limited by the surrounding rigid rock mass with high seismic velocity, such as the Lhasa block in the north and east, and Namcha Barwa complex in the south, and other aftershocks appearing at the NW top of GP and the SE side of Yarlung Tsangpo Big Bend reflect the strong squeezing effect of the NB-GP massif to its northeastern geological mass.

Numerical Study on Earthquake Energy Partitioning: Relationships Among Radiated Energy, Seismic Moment, and Stress Drop

AbstractThis paper aims at mechanistically studying some aspects of earthquake energy partitioning with a focus on the radiated energy (Es) and seismic moment (Mo) relationships for investigating differences between estimates of average dynamic stress drop ( ) and static stress drop ( ). We evaluate to what extent a relatively simple but analytically verified faulting simulation can explain such differences. We adopt a numerical methodology developed in the 2‐D Universal Distinct Element Code to simulate fault slip with slip‐weakening responses. A method is introduced for recording the ground reaction to slip and from which we discuss the energy partitioning in ideal cases of rupture. We examine a shallow strike‐slip fault model where a locally peaked stress is gradually developed on the fault by applying tectonic stresses away from the fault surface until a rupture is initiated locally and propagated outward. The rupture is terminated when the available energy is exhausted by the fracture energy and friction work especially as the rupture is followed by a creep. With investigating roles of the available energy for rupture and the fracture energy, we display limited cases where Mo does not, at least proportionately, scale with Es. Results show this is because Mo, compared to Es, does not fully represent the energy available for initiating a rupture and the fracture energy consumed during its propagation. That is why 2μEs/Mo and 2μEs/ηRMo estimates, with the radiation ratio ηR and rigidity μ, may significantly differ from and .

Mechanical behavior of Deveci pear cultivar affected by maturation

The present study examines the mechanical behavior of ‘Deveci’ pear cultivar produced in Turkey in terms of harvesting periods. Penetration tests were applied to the determined sides (bloom side, lateral side and stem side) of pear fruit harvested on three different maturation dates (October 5-15-25). According to the test results, it was found that harvesting period had different effects on mechanical properties of pears. Decrease was found in rupture force, rupture energy, deformation and firmness values of pears as the harvest date progressed. Rupture force values were as 52.69, 45.56 and 41.95 N in the first, second and third harvesting dates, respectively. Deformation was 5.57 in the first harvesting date and as 5.12 mm in the third harvesting date. The present study showed that firmness values of mature pear fruit were less. Firmness value was 9.59 N/mm in the first harvesting date and 8.09 N/mm in the third harvesting date. The highest firmness value was found on the stem side of pears.

On energy relationships between explosive rupture and extraction processes at quarries

The article deals with the links between mineral extraction processes. The most universal characteristic of the process is its energy intensity. Production process cycles are considered in the relationship between their energy characteristics, taking into account the extraction in the working face over time. This approach has been largely determined by earlier studies in the direction of studying the energy intensity of technological processes. However, the relationship between explosive rupture energy and excavation has not been established, although the link between explosive preparation and the performance of the excavation equipment was stated in the technical literature multiple times. The presented material analyzed previously published materials on establishing relationships between drilling and explosive rupture processes of rock massif. The energy characteristics of excavation works and explosive rupture were considered. Prospective direction of technological links study was proposed. Attention is drawn to the fact that the approach to relationships definition between processes may not always be monotonous, because it is sometimes difficult to express physical meaning in a flat system.

The effects of compression speed and positions on some cracking characteristics and kernel extraction quality of hazelnuts cv. Sivri

Bu çalışmada farklı sıkıştırma hızları (0.5, 1.0, 1.5 ve 2 mm/s) ve yönlerinin (uzunluk, genişlik ve kalınlık), Sivri fındık çeşidinde bazı kırılma özellikleri (kırma kuvveti, kırma enerjisi ve özgül deformasyon) ile iç çıkma kalitesi üzerine etkileri belirlenmiştir. Ayrıca kabuk kalınlığı ve geometrik ortalama çap değerleriyle bu kırılma özellikleri ve iç çıkma kalitesi arasındaki ilişki incelenmiştir. Bu amaçla 16.40 mm’den büyük ve küçük olan iki grup kabuklu fındık örneği üniversal tekstür cihazıyla sıkıştırma testlerine tabi tutulmuştur. En düşük kırılma kuvveti (167 N) ve enerjisi (105 J) uzunluk yönünden kuvvet uygulanan ikinci grup fındıklarda bulunmuştur. İncelenen fındık örneklerinde geometrik ortalama çap ve kabuk kalınlıklarının, kabuk kırılma özelliklerini önemli şekilde etkilediği bulunmuştur. Kabuk kalınlığı ve geometrik ortalama çap arttıkça genellikle kabuk kırılma kuvveti ve kırılma enerjisi artmış, özgül deformasyon ise düşmüştür. Yükleme hızı arttıkça birinci grup meyvelerde kırılma için ihtiyaç duyulan kuvvet ve enerji artarken, ikinci grupta bu değişim kararlılık göstermemiştir. Tüm kombinasyonlarda kırılma hızı artıkça iç çıkma kalitesi bariz olarak azalmıştır. Geometrik ortalama çap ile iç çıkma kalitesi arasında herhangi bir ilişki saptanamamıştır. Sonuç olarak iki grup için ortalama değerler dikkate alındığında en düşük kırılma kuvveti (199.5 N) uzunluk yönünden yapılan testlerde elde edilirken, iç çıkma kalitesi bakımından en iyi sonucu (5.00) genişlik ekseninde kırılan fındıklar vermiştir. Sivri fındık çeşidi için incelenen hızlar dikkate alındığında kaliteli iç eldesi için 1 mm/s’nin üzerindeki kırma hızları önerilmemektedir.

The physical properties and strength characteristics of kenaf plants

This article reports some physical properties and strength characteristics of two kenaf (Hibiscus cannabinus) varieties in Nigeria at critical stages of harvest with a view of understanding the plant material reaction to the load and deformation. The kenaf samples were subjected to a uniaxial compression test between two parallel plates at a loading rate of 20 mm·min&lt;sup&gt;–1&lt;/sup&gt; and a uniaxial bending test between two supports on each end at a loading rate of 50 mm·min&lt;sup&gt;–1 &lt;/sup&gt;using a Universal Instron Testing Machine (Instron, USA). The results of the parameters studied revealed that Tianung 1 gave the higher stem height, stem diameter, compressive stress, bending stress, rupture load, rupture energy, Young’s modulus, and toughness, which were 293.10 cm, 18.45 mm, 8.70 MPa, 44.86 MPa, 191.51 N, 3.43 J·mm&lt;sup&gt;–2&lt;/sup&gt;, 350.81 MPa, and 6.85 N·mm&lt;sup&gt;–1&lt;/sup&gt;, respectively, at four months after planting. The parameters studied significantly increased with maturity for the two kenaf varieties. However, the moisture content significantly reduced with maturity.

ANALISIS PARAMETER SUMBER SPEKTRAL GEMPABUMI VTA (VULKANO TEKTONIK-A) TERHADAP AKTIVITAS VULKANIK GUNUNG SINABUNG

The source parameters describe the different physical properties of seismic volumes under the volcanoes. Source parameters that can be used to distinguish seismic events that are generated by different types of volcanoes activities. Temporary changes of the spectral source parameters provided a description of the main events during the eruption process. Source parameters are calculated by correlating the relationship between source frequency at spectral displacement (corner frequency) and source parameters based on spectral sources of the Brune model (1970). The angular frequency obtained by applying the FFT algorithm to the VTA spectral displacement. The source parameters analyzed from this VTA earthquake are the spectral slope, seismic moment, stress drop, length of rupture, moment magnitude and radiation energy. Based on the obtained corner frequency (12 Hz-13 Hz), seismic moment, moment magnitude and energy radiation respectively were at 0.2 -1.9 x 1012 Nm, 0.7 - 2 Mw, and 0.1 - 9.5 x 1015 erg. The length of rupture were from 144.2 to 243.1 m, the spectra slope has 2.1 - 7.8 dB/cm, and stress drop are 0.1 - 7,6 bar. From the results of this study, it can be concluded that the changes of spectra characteristic and fluctuate of source patrameters value of VTA earthquakes was asosiated with the different volcanic activity of Sinabung.&#x0D; Keywords: spectral, VTA, source parameter, volcanic earthquake

Effects of shape feature on compression characteristics and crack rules of maize kernel

The physical and compression properties were analyzed for three kernel shapes of hybrid maize, Dika 517 and Denghai 618, grown under the same agroecological conditions. The average forces required to rupture the kernels of Dika 517 and Denghai 618 were 150.35 ± 80.90 N and 161.74 ± 86.16 N, respectively, and the average kernel rupture energies were 134.25 ± 50.77 mJ and 137.78 ± 58.35 mJ, respectively. Pyramidal and rectangular shape kernels exhibited the largest rupture force and energy at the thickness position, and round kernels have the highest rupture force and energy at length. The energy absorbed by kernels increased with an increased loading rate. The law of cracking for various surfaces differed under different loading directions for different shape kernels. Practical applications The physical and mechanical properties of maize kernels are different because of their different shapes. Understanding the physical and mechanical properties of maize kernels is important to assess the product quality, but is also crucial for the effective design and development of equipment and structures for efficient sowing, harvesting, transporting, handling, and processing.

Mechanical Behavior of Apricot and Cherry Pits under Compression Loading

This study was conducted to investigate the mechanical behavior of apricot and cherry pits under compression loading along the three axial dimensions of the pits. The mechanical behavior was expressed in terms of force required to rupture of the pit, deformation at rupture point, deformation ratio (strain), energy absorbed and toughness. Also; masses and geometrical properties (axial dimensions, geometric mean diameter, sphericity and volume) of these pits were determined. These properties are necessary to design of cracking machines and knowledge amount of force and energy requirements for cracking operation. All experiments were carried out at moisture content of 9.81 and 12.92 %, (d.b.) for apricot and cherry pits, resp. The results showed that; the highest values of rupture force, deformation and energy required to crack the apricot pit were at loading position through the length axis, while; the lowest values were through the width axis, whereas; the highest values of rupture force, deformation and energy required to crack the cherry pit were at loading position through the thickness axis, while; the lowest values were through the width axis. In conclusion; the results obtained of the mechanical behavior of apricot and cherry pits indicated that; the compression through the width axis can be recommended for cracking process with minimum force and energy requirements.

Mechanical Behaviour of Common Bean (cv. Butter) Seeds as Affected by Maturation

In this study, the effects of maturation of bean seeds on some mechanical behaviours of common bean (cv. Butter) were investigated. The bean seeds were harvested at three maturity stages (15 DAPA, 22 DAPA and 29 DAPA), and their rupture force, rupture energy, specific deformation, toughness and rupture power were test. The bean seeds were quasi-statically loaded in along their three main axes (X-axis, Y-axis and Z-axis), at a loading speed of 25 mm/min. The results obtained revealed that the maturity stage and loading orientation had significant (p ≤0.05) effect on all the mechanical parameters investigated in this study. According to the results, all the parameters investigated increased linearly as the bean seeds matured from 15 DAPA to 29 DAPA. For all the mechanical parameters, the highest values were obtained when the seeds were compressed along the Z-axis, while the least values were obtained when the seeds were compressed along the Y-axis. The highest rupture energy (0.064 Nm) was obtained for bean seeds (harvested at 29 DAPA) loaded along the Z-axis, while the bean seeds harvested at 15 DAPA and loaded along the Y-axis required the least energy to rupture (0.028 Nm). From the results, at 29 DAPA, the mean rupture power of 0.277 W, 0.212 W, and 0.314 W were recorded, when the seeds were compressed along the X-axis, Y-axis and Z-axis respectively. These results will be useful in the design and development of bean seeds processing and handling equipment.

Influence of flame retardants on the mechanical properties of glass fiber reinforced compounds in polymeric matrix epoxy and polyester

In the present study, polymeric epoxy and polyester resin reinforced with glass fiber compounds were prepared by adding of flame retardants based on aluminum and magnesium hydroxide in order to evaluate their influence on mechanical properties. An experimental DOE design was developed with two qualitative factors: the resin and retardant type; with two levels each and a quantitative factor: volumetric composition of the retardant with three levels (3%, 6% and 9%). With all possible combinations; tensile, flexural and impact tests were carried out. The results showed that the addition of retardants in different percentages has different influence for each mechanical property. It was evidenced that the 9% HA Aluminum Hydroxide has no significant effect on the tensile strength and its modulus compared to Magnesium Hydroxide HM. Conversely; on the flexural strength, flexural modulus and rupture energy the HM has a slightly lower effect with respect to the HA. For flexural strength and its modulus, the best proportion of retardant was 6%. 3% is the recommendation for rupture energy. The data presented in this document can be used to improve the fire resistance of the existing materials studied.

Cohesive-zone analyses with stochastic effects, illustrated by an example of kinetic crack growth

Cohesive-zone models of fracture are traditionally implemented using a deterministic failure criterion, with crack advance occurring when the work done against crack-tip tractions reaches a critical level. There are, however, many physical phenomena where crack growth is controlled by stochastic events ahead of the crack. These can include kinetic crack growth, stress-corrosion cracking, and void nucleation. In this paper, we show how a cohesive-zone model might be adapted to describe such stochastic phenomena. In particular, we have chosen to model kinetic crack growth by assuming that the probability of local failure, or bond rupture, depends on the difference between the level of local work done against the cohesive tractions and the equilibrium toughness of the interface. We have shown that if the cohesive parameters are within a range appropriate for linear-elastic fracture mechanics (LEFM), and the possibility of failure is limited to the crack tip, then the model accurately reproduces a classical analytical model for kinetic crack growth, with the crack velocity having an exponential relationship with respect to the level of the energy-release rate above a threshold. As with all cohesive-zone models, a transition between toughness-controlled fracture and strength-controlled fracture occurs as the cohesive length is increased. However, it is further noted that if failure is not limited to the crack tip, but is allowed to occur anywhere ahead of the crack tip, then the length scale controlling the crack velocity changes from the mesh size to the cohesive length. This mesh-independent result is associated with diffuse damage ahead of the crack tip. From a physical perspective, such a damage zone could correspond to a situation with a low activation energy for bond rupture, or to one where the a crack grows in response to spatially diffuse stochastic process in a damage zone such as void nucleation, crazing or micro-cracking.

Evaluation of physicochemical properties, antioxidant potential and baking quality of grain and flour of primitive rye (Secale cereale var. Multicaule)

The consumers interest in organic food and farmers’ search for cultivars with increased usefulness for organic farming have contributed to the revival of ancient cereal species and their launch onto the food market. In view of the above, the aim of this study was to determine the physicochemical properties, antioxidant potential and baking quality of grain and flour of primitive rye (Secale cereale var. Multicaule Polish: Krzyca), and to compare these parameters with open-pollinated and hybrid cultivars of common rye. The following determinations were made: the morphological and mechanical properties of grain, milling energy and the protein, starch, ash and free phenolic content of the analyzed flours, their amylograph characteristics and antioxidant potential. It was found that primitive rye has shorter kernels, lower thousand-kernel weight and a higher contribution of redness in color compared with common rye. In primitive rye grain rupture force was determined at 68.9 N and rupture energy at 35.6 mJ. Flours made from primitive rye grain have a higher content of ash and free phenolic compounds, lower starch content and similar antioxidant potential relative to common rye flours. The results of the amylograph test revealed that primitive rye flours were characterized by high baking quality. The primitive rye flours can be alternative ingredients for bread making and provide health advantage such as higher content of phenolic compounds. However, further research is needed to analyze variations in the properties of primitive rye grain and flour resulting from changes in environmental and climatic conditions.

EFFECT OF STORAGE DURATION ON MECHANICAL PROPERTIES OF BELLO EGGPLANT FRUIT UNDER QUASI COMPRESSION LOADING

The mechanical properties of eggplant fruit (cv. Bello) harvested at physiological maturity stage were evaluated in three storage periods (3d, 6d and 9d). These mechanical parameters (rupture force, rupture energy and deformation at rupture point) were measured under quasi compression loading, using the Universal Testing Machine (Testometric model). The fruit’s toughness and rupture power were calculated from the data obtained from the rupture energy and deformation at rupture point. Results obtained showed that mechanical properties of the Bello eggplant fruit exhibited strong dependence on the storage period. The results showed that as the Bello fruit stored longer, its rupture force and rupture energy decreased from 812 N to 411 N, and 5.58 Nm to 3.11 Nm respectively. While the rupture power decreased from 1.095 W to 0.353 W. On the contrary, the toughness and deformation at rupture increased from 0.270 mJ/mm3 to 0.403 mJ/mm3, and 16.99 mm to 25.22mm respectively during the 9 days storage period. The knowledge of the mechanical properties of fruits is important for their harvest and post-harvest operations, therefore, information obtained from this study will be useful in the design and development of machines for the mechanization of eggplant production.

Instrumental measurement of pomegranate texture during four maturity stages.

Texture of pomegranate fruit and arils are the main quality attributes in the food process industries. In this study, the texture properties of pomegranate fruit and arils (cv. "Ashraf") at four different stage of maturity (88, 109, 124, and 143 days after full bloom) were evaluated using the puncture test (rupture force and rupture energy) and compression test (bioyield force, rupture energy, and young modulus). The tests showed that all studied textural parameters were sensitive textural parameters for distinguishing the maturity stages. Rupture force and rupture energy of pomegranate fruit were determined at top, middle, and bottom positions of the fruit. The results showed that compression load values of aril increased with advances in maturity stage of fruit, while puncture load values of fruit decreased. The textural properties of pomegranate fruit and arils exhibited a strong dependence (p < .05) on the degree of maturity at harvesting time. Also results showed that rupture force of three different studied positions of fruit was severely different. The highest and lowest values were observed at top and middle position, respectively.