Search results for: Empty fruit bunch fibers

Authors: F. Z. Yekeler, H. Ozyurek, C. E. Tamer

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Fruits and vegetables are the essentials of a healthy diet, mainly because of their antioxidant properties contributing to disease blockage especially for some certain types of cancer. Being a favourite fruit, citrus are produced for economic and commercial purposes worldwide. Particularly, lemon fruit (Citrus limon L.), has an important place in export products of Turkey. Lemon has a great importance on human nutrition with regard to being a source of nutrients, flavonoids, vitamin C and minerals. It is used for food flavouring and pickling and also processed for lemonade. By processing citrus into fruit juices, consumption may increase and also become easier. Like many fruits and vegetables lemons are cheap and abundant during harvesting period, while they are quite expensive in other seasons. Lemon juice and concentrate production allows consumers to get benefits from lemon fruit in any time of the year. Lemonade is getting in to the focus of consumers’ attention preferring non-carbonated drinks. The demand of healthy, convenient functional foods affects consumer trends through innovative products. For this reason, lemonade could be enriched with different natural herb extracts such as ginger (Zingiber officinale), linden (Tilia cordata), and mint (Mentha piperita).

Keywords: Lemonade, herb extracts, antioxidant activity.

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Authors: Orathai Wongmetha, Lih-Shang Ke

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The quality attributes and storage life of 'Jinhwang' mango fruit can be effectively maintained with 1-methylcyclopropene (1-MCP) application and/or chitosan coating. 'Jinhwang' mango fruit was treated with 5 μl l-1 1-MCP for 12 h, dipped with 0.5 % chitosan, 5 μl l-1 1-MCP combine with 0.5 % chitosan and untreated (control) then stored at 10oC. Mango treated with 1-MCP maintained firmness, sucrose and starch content. Chitosan coating delayed firmness loss, sucrose content and the fruit decay when compare with control. Application of 1-MCP combine with chitosan also delayed firmness loss, sucrose content and starch content during storage. Furthermore, chitosan coating and combine treatment prolonged storage life of mango up to 29 days after storage while 1-MCP extended to 28 days after storage. Therefore, using all application of chitosan coating or 1-MCP combine with chitosan or 1-MCP in mango at 10oC is a feasible technology for maintains quality and prolongs storage life in order to expand marketability and export options.

Keywords: 1-Methylcyclopropene (1-MCP), chitosan, quality, storage life

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Authors: Adilson M. Enes, Juliana A. Fracarolli, Inácio M. Dal Fabbro, Silvestre Rodrigues

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This research work proposed a study of fruit bruise detection by means of a biospeckle method, selecting the papaya fruit (Carica papaya) as testing body. Papaya is recognized as a fruit of outstanding nutritional qualities, showing high vitamin A content, calcium, carbohydrates, exhibiting high popularity all over the world, considering consumption and acceptability. The commercialization of papaya faces special problems which are associated to bruise generation during harvesting, packing and transportation. Papaya is classified as climacteric fruit, permitting to be harvested before the maturation is completed. However, by one side bruise generation is partially controlled once the fruit flesh exhibits high mechanical firmness. By the other side, mechanical loads can set a future bruise at that maturation stage, when it can not be detected yet by conventional methods. Mechanical damages of fruit skin leave an entrance door to microorganisms and pathogens, which will cause severe losses of quality attributes. Traditional techniques of fruit quality inspection include total soluble solids determination, mechanical firmness tests, visual inspections, which would hardly meet required conditions for a fully automated process. However, the pertinent literature reveals a new method named biospeckle which is based on the laser reflectance and interference phenomenon. The laser biospeckle or dynamic speckle is quantified by means of the Moment of Inertia, named after its mechanical counterpart due to similarity between the defining formulae. Biospeckle techniques are able to quantify biological activities of living tissues, which has been applied to seed viability analysis, vegetable senescence and similar topics. Since the biospeckle techniques can monitor tissue physiology, it could also detect changes in the fruit caused by mechanical damages. The proposed technique holds non invasive character, being able to generate numerical results consistent with an adequate automation. The experimental tests associated to this research work included the selection of papaya fruit at different maturation stages which were submitted to artificial mechanical bruising tests. Damages were visually compared with the frequency maps yielded by the biospeckle technique. Results were considered in close agreement.

Keywords: Biospeckle, papaya, mechanical damages, vegetable bruising.

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Authors: K. Mohammed, M. Agarwal, J. Mewman, Y. Ren

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An optimum technic has been developed for extracting volatile organic compounds which contribute to the aroma of lime fruit (Citrus aurantifolia). The volatile organic compounds of healthy and infested lime fruit with California red scale Aonidiella aurantii were characterized using headspace solid phase microextraction (HS-SPME) combined with gas chromatography (GC) coupled flame ionization detection (FID) and gas chromatography with mass spectrometry (GC-MS) as a very simple, efficient and nondestructive extraction method. A three-phase 50/30 μm PDV/DVB/CAR fibre was used for the extraction process. The optimal sealing and fibre exposure time for volatiles reaching equilibrium from whole lime fruit in the headspace of the chamber was 16 and 4 hours respectively. 5 min was selected as desorption time of the three-phase fibre. Herbivorous activity induces indirect plant defenses, as the emission of herbivorous-induced plant volatiles (HIPVs), which could be used by natural enemies for host location. GC-MS analysis showed qualitative differences among volatiles emitted by infested and healthy lime fruit. The GC-MS analysis allowed the initial identification of 18 compounds, with similarities higher than 85%, in accordance with the NIST mass spectral library. One of these were increased by A. aurantii infestation, D-limonene, and three were decreased, Undecane, α-Farnesene and 7-epi-α-selinene. From an applied point of view, the application of the above-mentioned VOCs may help boost the efficiency of biocontrol programs and natural enemies’ production techniques.

Keywords: Lime fruit, Citrus aurantifolia, California red scale, Aonidiella aurantii, VOCs, HS-SPME/GC-FID-MS.

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Authors: Sami I. Serhan, Hamed M. Abdel-Haq

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In this paper, an efficient technique is proposed to manage the cache memory. The proposed technique introduces some modifications on the well-known set associative mapping technique. This modification requires a little alteration in the structure of the cache memory and on the way by which it can be referenced. The proposed alteration leads to increase the set size virtually and consequently to improve the performance and the utilization of the cache memory. The current mapping techniques have accomplished good results. In fact, there are still different cases in which cache memory lines are left empty and not used, whereas two or more processes overwrite the lines of each other, instead of using those empty lines. The proposed algorithm aims at finding an efficient way to deal with such problem.

Keywords: Modified Set Associative Mapping, Locality of Reference, Miss Ratio, Hit Ratio, Cache Memory, Clustered Behavior, Index Address, Tag Field, Status Field, and Complement of Index Address.

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Authors: R. Aminzadeh, M. Abarzani, J. Sargolzaei

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In this study, the kinetics of osmotic dehydration of melons (Tille variety) in a ternary system followed by air-drying for preserving melons in the summer to be used in the winter were investigated. The effect of different osmotic solution concentrations 30, 40 and 50% (w/w) of sucrose with 10% NaCl salt and fruit to solution ratios 1:4, 1:5 and 1:6 on the mass transfer kinetics during osmotic dehydration of melon in ternary solution namely sucrosesalt- water followed by air-drying were studied. The diffusivity of water during air-drying was enhanced after the fruit samples were immersed in the osmotic solution after 60 min. Samples non-treated and pre-treated during one hour in osmotic solutions with 60% (w/w) of sucrose with 10% NaCl salt and fruit to solution ratio of 1:4 were dried in a hot air-dryer at 60oC (2 m/s) until equilibrium was achieved.

Keywords: Air drying, Effective diffusion coefficient, Mass transfer kinetic, Melon, Osmotic dehydration.

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Authors: M. Maleki, M. Latifi, M. Amani-Tehran

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Nano fibers produced by electrospinning are of industrial and scientific attention due to their special characteristics such as long length, small diameter and high surface area. Applications of electrospun structures in nanotechnology are included tissue scaffolds, fibers for drug delivery, composite reinforcement, chemical sensing, enzyme immobilization, membrane-based filtration, protective clothing, catalysis, solar cells, electronic devices and others. Many polymer and ceramic precursor nano fibers have been successfully electrospun with diameters in the range from 1 nm to several microns. The process is complex so that fiber diameter is influenced by various material, design and operating parameters. The objective of this work is to apply genetic algorithm on the parameters of electrospinning which have the most significant effect on the nano fiber diameter to determine the optimum parameter values before doing experimental set up. Effective factors including initial polymer concentration, initial jet radius, electrical potential, relaxation time, initial elongation, viscosity and distance between nozzle and collector are considered to determine finest diameter which is selected by user.

Keywords: Electrospinning, genetic algorithm, nano fiber diameter, optimization.

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Authors: D. Zare, H. Safiyari, F. Salmanizade

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In this study, some physical and mechanical properties of jujube fruits, were measured and compared at constant moisture content of 15.5% w.b. The results showed that the mean length, width and thickness of jujube fruits were 18.88, 16.79 and 15.9 mm, respectively. The mean projected areas of jujube perpendicular to length, width, and thickness were 147.01, 224.08 and 274.60 mm2, respectively. The mean mass and volume were 1.51 g and 2672.80 mm3, respectively. The arithmetic mean diameter, geometric mean diameter and equivalent diameter varied from 14.53 to 20 mm, 14.5 to 19.94 mm, and 14.52 to 19.97 mm, respectively. The sphericity, aspect ratio and surface area of jujube fruits were 0.91, 0.89 and 926.28 mm2, respectively. Whole fruit density, bulk density and porosity of jujube fruits were measured and found to be 1.52 g/cm3, 0.3 g/cm3 and 79.3%, respectively. The angle of repose of jujube fruit was 14.66° (±0.58°). The static coefficient of friction on galvanized iron steel was higher than that on plywood and lower than that on glass surface. The values of rupture force, deformation, hardness and energy absorbed were found to be between 11.13-19.91N, 2.53- 4.82mm, 3.06-5.81N mm and 20.13-39.08 N/mm, respectively.

Keywords: Mechanical and Physical properties, Jujube fruits, friction coefficient

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Authors: Loai Ben Naji, Osama M. Ibrahim, Khaled J. Al-Fadhalah

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The objective of this paper is to investigate the formation and adhesion of a protective aluminum-oxide (Al₂O₃, alumina) layer on the surface of Iron-Chromium-Aluminum Alloy (Fe-Cr-Al) sintered-metal-fibers. The oxide-scale layer was developed via multi-stage thermal oxidation at 930 ^oC for 1 hour, followed by 1 hour at 960 ^oC, and finally at 990 ^oC for 2 hours. Scanning Electron Microscope (SEM) images show that the multi-stage thermal oxidation resulted in the formation of predominantly Al₂O₃ platelets-like and whiskers. SEM images also reveal non-uniform oxide-scale growth on the surface of the fibers. Furthermore, peeling/spalling of the alumina protective layer occurred after minimum handling, which indicates weak adhesion forces between the protective layer and the base metal alloy.  Energy Dispersive Spectroscopy (EDS) analysis of the heat-treated Fe-Cr-Al sintered-metal-fibers confirmed the high aluminum content on the surface of the protective layer, and the low aluminum content on the exposed base metal alloy surface. In conclusion, the failure of the oxide-scale protective layer exposes the base metal alloy to further oxidation, and the fragile non-uniform oxide-scale is not suitable as a support for catalysts.

Keywords: High-temperature oxidation, alumina protective layer, iron-chromium-aluminum alloy, sintered-metal-fibers.

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Authors: Djemaa Megdoud, Messaoud Boudaa, Fatima Ouamrane, Salem Benamara

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In recent years, the compression of date (Phoenix dactylifera L.) fruit powders (DP) to obtain date tablets (DT) has been suggested as a promising form of valorization of non commercial valuable date fruit (DF) varieties. To further improve and characterize DT, the present study aims to investigate the influence of the DP particle size and compression force on some physical properties of DT. The results show that independently of particle size, the hardness (y) of tablets increases with the increase of the compression force (x) following a logarithmic law (y = a ln (bx) where a and b are the constants of model). Further, a full factorial design (FFD) at two levels, applied to investigate the erosion %, reveals that the effects of time and particle size are the same in absolute value and they are beyond the effect of the compression. Regarding the disintegration time, the obtained results also by means of a FFD show that the effect of the compression force exceeds 4 times that of the DP particle size. As final stage, the color parameters in the CIELab system of DT immediately after their obtaining are differently influenced by the size of the initial powder.

Keywords: Powder, valorization, tablets, date fruit (Phoenix dactylifera L.), hardness, erosion, disintegration time, color.

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Authors: Min Ho Kwon, Woo Young Jung, Hyun Su Seo

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A polymer cement mortar (PCM) has been widely used  as the material of repair and restoration work for concrete structure;  however a PCM usually induces an environmental pollutant.  Therefore, there is a need to develop PCM which is less impact to  environments. Usually, UM resin is known to be harmless to the  environment. Accordingly, in this paper, the properties of the PCM  using UM resin were studied. The general cement mortar and UM  resin were mixed in the specified ratio. A certain percentage of PVA  fibers, steel fibers and mixed fibers (PVA fiber and steel fiber) were  added to enhance the flexural strength. The flexural tests were  performed in order to investigate the flexural strength of each PCM.  Experimental results showed that the strength of proposed PCM using  UM resin is improved when they are compared with general cement  mortar.

 

Keywords: Polymer cement mortar (PCM), UM resin, Compressive strength, PVA fiber, Steel fiber.

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Authors: S. Al-Sowayan

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The impact of selective excitation of circular helical modes of graded-index fibers on its capacity is analyzed using a model for propagation delay variation with launch offset and angle that resulted from misalignment of source and fiber axis. Results show promising technique to improve graded-index fiber capacities.

Keywords: Fiber measurements, Fiber optic communications.

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Authors: Himali N. Balasooriya, Kithsiri B. Dassanayake, Saman Seneweera, Said Ajlouni

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Increase in atmospheric CO₂ concentration [CO₂] and ambient temperature associated with changing climatic conditions will have significant impacts on agriculture crop productivity and quality. Independent effects of the above two environmental variables on the growth, yield and quality of strawberry were well documented. Higher temperatures over the optimum range (20-25ºC) lead to crop failures, while elevated [CO₂] stimulated plant growth and yield but compromised the physical quality of fruits. However, there is very limited understanding of the interaction between these variables on the plant growth, yield and quality. Therefore, this study was designed to investigate the interactive effect of high temperature and elevated [CO₂] on growth, yield and quality of strawberries. Strawberry cultivars ‘Albion’ and ‘San Andreas’ were grown under six different combinations of two temperatures (25 and 30ºC) and three [CO₂] (400, 650 and 950 µmol mol^-1) in controlled-environmental growth chambers. Plant growth measurements such as plant height, canopy area, number of flowers, and fruit yield were measured during phonological development. Photosynthesis and transpiration, the ratio of intercellular to atmospheric [CO₂] (Ci/Ca) were measured to estimate the physiological adjustment to climate stress. The impact of temperature and [CO₂] interaction on growth and yield of strawberry was significant (p < 0.05). Across both cultivars, highest fruit yields were observed at 650 µmol mol^-1 [CO₂], which was particularly clear at 25°C. The fruit yield gradually decreased at 30°C under all the treatment combinations. However, photosynthesis rates were highest at 650 µmol mol^-1 [CO₂] but no increment was found at 900 µmol mol^-1 [CO₂]. Interestingly, Ci/Ca ratio increased with increasing atmospheric [CO₂] which was predominant at high temperature. Similarly, fruit yield was substantially reduced at high [CO₂] under high temperature. Our findings suggest that increased Ci/Ca ratio at high temperature is likely reduces the photosynthesis and thus yield response to elevated [CO₂].

Keywords: Atmospheric [CO2], fruit yield, strawberry, temperature.

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Authors: Musa Seymen, Duran Yavuz, Nurcan Yavuz, Önder Türkmen

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Edible seed pumpkin (Cucurbita pepo L.) is one of the important edibles preferred by consumer in Turkey due to its higher nutrient contents. However, there is almost very few study on water consumption and irrigation water requirement of confectionary edible seed pumpkin in Turkey. Therefore, a 2-year study (2013-2014) was conducted to determine the effects of irrigation levels on the seed yield and yield components of drip-irrigated confectionary edible seed pumpkin under Turkey conditions. In the study, the experimental design was made in randomized blocks with three replications. Treatments consisted of five irrigation water levels that compensated for the 100% (I₁₀₀, full irrigation), 75% (I₇₅), 50% (I₅₀), 25% (I₂₅) and 0% (I₀, no irrigation) of crop water requirements at 14-day irrigation intervals. Seasonal evapotranspiration of treatments varied from 194.2 to 625.2 mm in 2013 and from 208.6 to 556.6 mm in 2014. In both years, the highest seasonal evapotranspiration was obtained in I₁₀₀ treatment. Average across years, the seed yields ranged between 1090 (I₁₀₀) and 422 (I₀) kg ha^-1. The irrigation treatments were found to significantly affect the yield parameters such as the seed yield, oil seed yield number of seeds per fruit, seed size, seed width, fruit size, fruit width and fruit index.

Keywords: Irrigation level, edible seed pumpkin, seed quality, seed yield.

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Authors: N. N. A. K. Shah, R. A. Rahman, R. Shamsuddin, N. M. Adzahan

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Pummelo is known to be the largest of all citrus fruits, with expected ratio of 2:1 (w/v) of producing juice, is an attractive opportunity for Malaysia to expand pummelo-s influence and marketability over the international market of juices. The purpose of this study is to identify and quantify the phenolic compounds in two Malaysian varieties of pummelo fruit juice: Ledang (PO55) and Tambun (PO52). Identifications of polyphenols composition were done using High Performance Liquid Chromatography Diode Array Detection (HPLC-DAD). The phenolic compounds that were found in both varieties were hydroxycinnamic acids and flavonones. This study proved that Tambun variety has the highest antioxidant and phenolic compounds in comparison to Ledang variety. However, considerations have to be made to suit consumer-s taste bud and the amount of enzyme needed to clarify the juice for its marketability.

Keywords: Antioxidant, HPLC, phenolic contents and pummelo fruit juice

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Authors: A. Bárbara Cattozatto Fortunato, D. de Lucca Soave, E. Pinheiro de Mello, M. Piasentini Oliva, V. Tavares de Moraes, G. Wolf Lebrão, D. Fernandes Parra, S. Marraccini Giampietri Lebrão

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Due to increasing environmental pressure for biodegradable products, especially in polymeric materials, in order to meet the demands of the biological cycles of the circular economy, new materials have been developed as a sustainability strategy. This study proposes a composite material developed from the biodegradable polymer PLA Ecovio® (polylactic acid - PLA) with natural sisal fibers, where the soybean ester was used as a plasticizer, which can aid in adhesion between the materials and fibers, making the most attractive final composite from an environmental point of view. The composites were obtained by extrusion. The materials tests were produced and submitted to biodegradation tests. Through the biodegradation tests, it can be seen that the biodegradable polymer composition with 5% sisal fiber presented about 12.4% more biodegradability compared to the polymer without fiber addition. It has also been found that the plasticizer was not a compatible with fibers and the polymer. Finally, fibers help to anticipate the decomposition process of the material when subjected to conditions of a landfill. Therefore, its intrinsic properties are not affected during its use, only the biodegradation process begins after its exposure to landfill conditions.

Keywords: Biocomposites, sisal, polylactic acid, PLA.

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Authors: Zoe Chang, Max Williams, Gautham Das

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The purpose of this study is to evaluate the incorporation of hemp fibers (HF) in concrete. Hemp fiber reinforced concrete (HFRC) is becoming more popular as an alternative for regular mix designs. This study was done to evaluate the compressive strength of HFRC regarding mix procedure. HF were obtained from the manufacturer and hand processed to ensure uniformity in width and length. The fibers were added to concrete as both wet and dry mix to investigate and optimize the mix design process. Results indicated that the dry mix had a compressive strength of 1157 psi compared to the wet mix of 985 psi. This dry mix compressive strength was within range of the standard mix compressive strength of 1533 psi. The statistical analysis revealed that the mix design process needs further optimization and uniformity concerning the addition of HF. Regression analysis revealed that the standard mix design had a coefficient of 0.9 as compared to the dry mix of 0.375 indicating a variation in the mixing process. While completing the dry mix, the addition of plain HF caused them to intertwine creating lumps and inconsistency. However, during the wet mixing process, combining water and HF before incorporation allows the fibers to uniformly disperse within the mix hence the regression analysis indicated a better coefficient of 0.55. This study concludes that HRFC is a viable alternative to regular mixes however more research surrounding its characteristics needs to be conducted.

Keywords: hemp fibers, hemp reinforced concrete, wet and dry, freeze thaw testing, compressive strength

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Authors: Özge Alptoğa, Nuray Uçar, Nilgün Karatepe Yavuz, Ayşen Önen

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Sulfur dioxide (SO₂) is a very toxic air pollutant gas and it causes the greenhouse effect, photochemical smog, and acid rain, which threaten human health severely. Thus, the capture of SO₂ gas is very important for the environment. Graphene which is two-dimensional material has excellent mechanical, chemical, thermal properties, and many application areas such as energy storage devices, gas adsorption, sensing devices, and optical electronics. Further, graphene oxide (GO) is examined as a good adsorbent because of its important features such as functional groups (epoxy, carboxyl and hydroxyl) on the surface and layered structure. The SO₂ adsorption properties of the fibers are usually investigated on carbon fibers. In this study, potential adsorption capacity of GO fibers was researched. GO dispersion was first obtained with Hummers’ method from graphite, and then GO fibers were obtained via wet spinning process. These fibers were converted into a disc shape, dried, and then subjected to SO₂ gas adsorption test. The SO₂ gas adsorption capacity of GO fiber discs was investigated in the fields of utilization of different coagulation baths and reduction by hydrazine hydrate. As coagulation baths, single and triple baths were used. In single bath, only ethanol and CaCl₂ (calcium chloride) salt were added. In triple bath, each bath has a different concentration of water/ethanol and CaCl₂ salt, and the disc obtained from triple bath has been called as reference disk. The fibers which were produced with single bath were flexible and rough, and the analyses show that they had higher SO₂ adsorption capacity than triple bath fibers (reference disk). However, the reduction process did not increase the adsorption capacity, because the SEM images showed that the layers and uniform structure in the fiber form were damaged, and reduction decreased the functional groups which SO₂ will be attached. Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) analyzes were performed on the fibers and discs, and the effects on the results were interpreted. In the future applications of the study, it is aimed that subjects such as pH and additives will be examined.

Keywords: Coagulation bath, graphene oxide fiber, reduction, SO2 gas adsorption.

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Authors: O. Alidoust, I. Sadrinejad, M. A. Ahmadi

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High strength concrete has been used in situations where it may be exposed to elevated temperatures. Numerous authors have shown the significant contribution of polypropylene fiber to the spalling resistance of high strength concrete. When cement-based composite that reinforced by polypropylene fibers heated up to 170 °C, polypropylene fibers readily melt and volatilize, creating additional porosity and small channels in to the matrix that cause the poor structure and low strength. This investigation develops on the mechanical properties of mortar incorporating polypropylene fibers exposed to high temperature. Also effects of different pozzolans on strength behaviour of samples at elevated temperature have been studied. To reach this purpose, the specimens were produced by partial replacement of cement with finely ground glass, silica fume and rice husk ash as high reactive pozzolans. The amount of this replacement was 10% by weight of cement to find the effects of pozzolans as a partial replacement of cement on the mechanical properties of mortars. In this way, lots of mixtures with 0%, 0.5%, 1% and 1.5% of polypropylene fibers were cast and tested for compressive and flexural strength, accordance to ASTM standard. After that specimens being heated to temperatures of 300, 600 °C, respectively, the mechanical properties of heated samples were tested. Mechanical tests showed significant reduction in compressive strength which could be due to polypropylene fiber melting. Also pozzolans improve the mechanical properties of sampels.

Keywords: Mechanical properties, compressive strength, Flexural strength, pozzolanic behavior.

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Authors: M. Yoshikawa, N. Tsuji, T. Yabuuchi, Y Shimomura, H. Kakigi, H. Hayashi, H. Ohgushi

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A scaffold is necessary for tooth regeneration because of its three-dimensional geometry. For restoration of defect, it is necessary for the scaffold to be prepared in the shape of the defect. Sponges made from polyvinyl alcohol with formalin cross-linking (PVF sponge) have been used for scaffolds for bone formation in vivo. To induce osteogenesis within the sponge, methods of growing rat bone marrow cells (rBMCs) among the fiber structures in the sponge might be considered. Storage of rBMCs among the fibers in the sponge coated with dextran (10 kDa) was tried. After seeding of rBMCs to PVF sponge immersed in dextran solution at 2 g/dl concentration, osteogenesis was recognized in subcutaneously implanted PVF sponge as a scaffold in vivo. The level of osteocalcin was 25.28±5.71 ng/scaffold and that of Ca was 129.20±19.69 µg/scaffold. These values were significantly higher than those in sponges without dextran coating (p<0.01). Osteogenesis was induced in many spaces in the inner structure of the sponge with dextran coated fibers.

Keywords: Dextran, Polyvinyl formal sponge, Osteogenesis, Scaffold.

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Authors: D. Scalone, R. Palmeri, F. Licciardello, G. Muratore, A. Todaro, G. Spagna

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Prickly pear fruit (Opuntia ficus indica L. Miller) belongs to the Cactaceae family. This species is very sensitive to low storage temperatures (< 5°C) which cause damages. The fruits can be peeled, suitably packaged and successfully commercialized as a ready-to-eat product. The main limit to the extension of the shelf life is the production of off-flavors due to different factors, the growth of microorganisms and the action of endogenous enzymes. Lipoxygenase (LOX) and Pectinesterase (PE) are involved in fruit degradation. In particular, LOX pathway is directly responsible for lipid oxidation, and the subsequent production of off-flavours, while PE causes the softening of fruit during maturation. They act on the texture and shelf-life of post-harvest, packaged fruits, as a function of the the grown of microorganisms and packaging technologies used. The aim of this work is to compare the effect of different packaging technologies on the shelf life extension of ready-to-eat prickly pear fruits with regards for the enzymes activities.

Keywords: Enzymes, packaging, prickly pear, shelf life.

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Authors: Chiung-Tsun Kuoa, Tzu-Hao Liu, Fang-Yi Lin, Tai-Hao Hsu, Hui-Yin Chen

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Hyperglycemia-mediated accumulation of advanced glycation end-products (AGEs) play a pivotal role in the development of diabetic complications by inducing inflammation. In the present study, we evaluated the possible effects of water/ethanol (1/1, v/v) extracts (WEE) and its fractions from Canarium album Raeusch. (Chinese olive) which is a fruit used on AGEs-stimulated oxidative stress and inflammation in monocytes and vascular endothelial cells. Co-incubation of EA.hy926 endothelial cells with WEE and its fractions for 24h resulted in a significant decrease of monocyte–endothelial cell adhesion, the expression of ICAM-1, generation of intracellular ROS and depletion of GSH induced by AGEs. Chinese olive fruit extracts also reduced the expression of pro-inflammatory mediates, such as TNF-α, IL-1β and IL-6 in THP-1 cells. These findings suggested that Chinese olive fruit was able to protect vascular endothelium from dysfunction induced by AGEs. 

Keywords: Advanced glycation end-products (AGEs), Canarium album Raeusch, endothelial dysfunction, inflammation.

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Authors: A. Mir, C. Aribi, B. Bezzazi

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Work presented is interested in the characterization of the quasistatic mechanical properties and in fatigue of a composite laminated in jute/epoxy. The natural fibers offer promising prospects thanks to their interesting specific properties, because of their low density, but also with their bio-deterioration. Several scientific studies highlighted the good mechanical resistance of the vegetable fiber composites reinforced, even after several recycling. Because of the environmental standards that become increasingly severe, one attends the emergence of eco-materials at the base of natural fibers such as flax, bamboo, hemp, sisal, jute. The fatigue tests on elementary vegetable fibers show an increase of about 60% of the rigidity of elementary fibers of hemp subjected to cyclic loadings. In this study, the test-tubes manufactured by the method infusion have sequences of stacking of 0/90° and ± 45° for the shearing and tensile tests. The quasistatic tests reveal a variability of the mechanical properties of about 8%. The tensile fatigue tests were carried out for levels of constraints equivalent to half of the ultimate values of the composite. Once the fatigue tests carried out for well-defined values of cycles, a series of static tests of traction type highlights the influence of the number of cycles on the quasi-static mechanical behavior of the laminate jute/epoxy.

Keywords: Jute, epoxy resin, mechanical, static, dynamic behavior.

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Authors: Amir Mahmoudi

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In this research the effects of adding silica and alumina nanoparticles on flow ability and compressive strength of cementitious composites based on Portland cement were investigated. In the first stage, the rheological behavior of different samples containing nanosilica, nanoalumina and polypropylene, polyvinyl alcohol and polyethylene fibers were evaluated. With increasing of nanoparticles in fresh samples, the slump flow diameter reduced. Fibers reduced the flow ability of the samples and viscosity increased. With increasing of the micro silica particles to cement ratio from 2/1 to 2/2, the slump flow diameter increased. By adding silica and alumina nanoparticles up to 3% and 2% respectively, the compressive strength increased and after decreased. Samples containing silica nanoparticles and fibers had the highest compressive strength.

Keywords: Portland cement, Composite, Nanoparticles, Compressive Strength.

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Authors: Fatih Sevim, Emel Sevimli, Fatih Demir, Turan Çalban

Abstract:

Nanofibers of PVA /nickel nitrate/silica/alumina izopropoxide/boric acid composite were prepared by using sol-gel processing and electrospinning technique. By high temperature calcinations of the above precursor fibers, nanofibers of NiO/Al2O3/B2O3/SiO2 composite with diameters about 500 nm could be successfully obtained. The fibers were characterized by XRD and SEM analyses.

Keywords: Nanofibers, ceramics composite, sol-gel processing, electrospinning.

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Authors: Mehrdad Ahmadi, Mohamad Babaie, Shiva Osouli, Bahareh Salehi, Nadia Kalantaraian

Abstract:

The olive fruit fly, Bactrocera oleae Gmelin (Diptera: Tephritidae), is one of the most serious pests in olive orchards in growing province in Iran. The female lay eggs in green olive fruit and larvae hatch inside the fruit, where they feed upon the fruit matters. One of the main ecologically friendly and species-specific systems of pest control is the sterile insect technique (SIT) which is based on the release of large numbers of sterilized insects. The objective of our work was to develop a SIT against B. oleae by using of gamma radiation for the laboratory and field trial in Iran. Oviposition of female mated by irradiated males is one of the main parameters to determine achievement of SIT. To conclude the sterile dose, pupae were placed under 0 to 160 Gy of gamma radiation. The main factor in SIT is the productivity of females which are mated by irradiated males. The emerged adults from irradiated pupae were mated with untreated adults of the same age by confining them inside the transparent cages. The fecundity of the irradiated males mated with non-irradiated females was decreased with the increasing radiation dose level. It was observed that the number of eggs and also the percentage of the egg hatching was significantly (P < 0.05) affected in either IM x NF crosses compared with NM x NF crosses in F₁ generation at all doses. Also, the statistical analysis showed a significant difference (P < 0.05) in the mean number of eggs laid between irradiated and non-irradiated females crossed with irradiated males, which suggests that the males were susceptible to gamma radiation. The egg hatching percentage declined markedly with the increase of the radiation dose of the treated males in mating trials which demonstrated that egg hatch rate was dose dependent. Our results specified that gamma radiation affects the longevity of irradiated B. oleae larvae (established from irradiated pupae) and significantly increased their larval duration. Results show the gamma radiation, and SIT can be used successfully against olive fruit flies.

Keywords: Fertility, olive fruit fly, radiation, SIT.

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Authors: Erika K. Méndez, Carlos E. Orrego, Diana L. Manrique, Juan D. Gonzalez, Doménica Vallejo

Abstract:

High moisture content in fruits generates post-harvest problems such as mechanical, biochemical, microbial and physical losses. Dehydration, which is based on the reduction of water activity of the fruit, is a common option for overcoming such losses. However, regular hot air drying could affect negatively the quality properties of the fruit due to the long residence time at high temperature. Power ultrasound (US) application during the convective drying has been used as a novel method able to enhance drying rate and, consequently, to decrease drying time. In the present study, a new approach was tested to evaluate the effect of US on the drying time, the final antioxidant activity (AA) and the total polyphenol content (TPC) of banana slices (BS), mango slices (MS) and guava slices (GS). There were also studied the drying kinetics with nine different models from which water effective diffusivities (Deff) (with or without shrinkage corrections) were calculated. Compared with the corresponding control tests, US assisted drying for fruit slices showed reductions in drying time between 16.23 and 30.19%, 11.34 and 32.73%, and 19.25 and 47.51% for the MS, BS and GS respectively. Considering shrinkage effects, Deff calculated values ranged from 1.67*10-10 to 3.18*10-10 m2/s, 3.96*10-10 and 5.57*10-10 m2/s and 4.61*10-10 to 8.16*10-10 m2/s for the BS, MS and GS samples respectively. Reductions of TPC and AA (as DPPH) were observed compared with the original content in fresh fruit data in all kinds of drying assays.

Keywords: Banana, drying, effective diffusivity, guava, mango, ultrasound.

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Authors: D. Salari, A. Niaei, P. Chitsaz Yazdi, M. Derakhshani, S. R. Nabavi

Abstract:

This work aims to test the application of computational fluid dynamics (CFD) modeling to fixed bed catalytic cracking reactors. Studies of CFD with a fixed bed design commonly use a regular packing with N=2 to define bed geometry. CFD allows us to obtain a more accurate view of the fluid flow and heat transfer mechanisms present in fixed bed equipment. Naphtha was used as feedstock and the reactor length was 80cm. It is divided in three sections that catalyst bed packed in the middle section of the reactor. The reaction scheme was involved one primary reaction and 24 secondary reactions. Because of high CPU times in these simulations, parallel processing have been used. In this study the coke formation process in fixed bed and empty tube reactor was simulated and coke in these reactors are compared. In addition, the effect of steam ratio and feed flow rate on coke formation was investigated.

Keywords: Coke Formation, CFD Simulation, Fixed Bed, Catalyitic Cracking.

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Authors: L. Slimani, A. Bousri, A. Hamadouche, H. Ben Hamed

Abstract:

The aim of this experimental and numerical study is to analyze the effects of acoustic streaming generated by 40 kHz ultrasonic waves on heat transfer in forced convection, with and without 40 PPI aluminum metal foam. Preliminary dynamic and thermal studies were done with COMSOL Multiphase, to see heat transfer enhancement degree by inserting a 40PPI metal foam (10 × 2 × 3 cm) on a heat sink, after having determined experimentally its permeability and Forchheimer's coefficient. The results obtained numerically are in accordance with those obtained experimentally, with an enhancement factor of 205% for a velocity of 0.4 m/s compared to an empty channel. The influence of 40 kHz ultrasound on heat transfer was also tested with and without metallic foam. Results show a remarkable increase in Nusselt number in an empty channel with an enhancement factor of 37,5%, while no influence of ultrasound on heat transfer in metal foam presence.

Keywords: Enhancing heat transfer, metal foam, ultrasound, acoustic streaming, laminar flow.

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Authors: Alessandro Bevilacqua, Alessandro Gherardi, Ludovico Carozza, Filippo Piccinini

Abstract:

The last years have seen an increasing use of image analysis techniques in the field of biomedical imaging, in particular in microscopic imaging. The basic step for most of the image analysis techniques relies on a background image free of objects of interest, whether they are cells or histological samples, to perform further analysis, such as segmentation or mosaicing. Commonly, this image consists of an empty field acquired in advance. However, many times achieving an empty field could not be feasible. Or else, this could be different from the background region of the sample really being studied, because of the interaction with the organic matter. At last, it could be expensive, for instance in case of live cell analyses. We propose a non parametric and general purpose approach where the background is built automatically stemming from a sequence of images containing even objects of interest. The amount of area, in each image, free of objects just affects the overall speed to obtain the background. Experiments with different kinds of microscopic images prove the effectiveness of our approach.

Keywords: Microscopy, flat field correction, background estimation, image segmentation.

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