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Evaluation of Physicochemical and Antioxidant Properties of Pinus gerardiana Nuts and Oil
Get PDFFor optimal usage of new oil resources with high nutritional values, in this study, one chilgoza pine variety was provided, and assays of physicochemical characteristics of its nut such as moisture, ash, thousand nut weight, oil, protein, hull contents, density, pH and also physicochemical characteristics of its extracted oil by n-hexan solvent such as iodine values, saponification and unsaponification, peroxide, specific weight, acid values, moisture of oil, color (Lovibond) and fatty acid profile and extracted oil characteristics by cold press such as total polyphenols, tocophrols, carotenoids, chlorophylls, sterols, color (Hunterlab), DPPḢ and antioxidant were investigated. Then its effect as a natural antioxidant on rapeseed oil shelf life (without any antioxidant) was studied. The results indicated that chilgoza pine oil is belonged to linoleic-oleic group. Oil of chilgoza pine has α and γ tocopherols and there is no β and δ tocopherols on it. The oil of chilgoza pine, were mixed at two levels of 2% and 5% with rapeseed oil and these mixed were determined by peroxide, TBA and Rancimat indices during 0, 5, 10, 20 and 35 days and compared with control. Statistical results showed no antioxidant effect in shelf life of rapeseed oil at more days. This means that the chilgoza pine oil antioxidant compounds were not enough to prevent oxidative rancidity of rapeseed oil or maybe the antioxidant compounds of nuts were not migrated to oil
Design, Rheology and Physicochemical Characterizations of Oil-in-water Emulsions Stabilized by Waxy Starch Derivatives
Get PDFSimple emulsions (o/w) stabilized by octenyl succinic anhydrous (OSA) starch were studied. They were characterized by the evaluation of the rheological and physicochemical properties and, the observation under the light microscope in combination with granulometric analysis after formulation. The obtained results demonstrated the effects of the amount of OSA starch on the variation of the diameter of particles, stability of emulsions and their rheological behavior. The best characteristics were found in the emulsion with a ratio 40/60 (o/w) at high OSA starch concentration, because the substitution of the oil phase by the network created by the chains of the modified polysaccharides which could be the major factor in stabilisation of emulsions
Skeletons of Glass Sponges as a Substrate for Creating Functional Composite Organosilicon Materials
Get PDFThe article describes a method of creating a three-dimensional organosilicon composite material based on the glass sponge spicules through a combination of soft etching and controlled mechanical action, non-destroying spicules. When in an alkaline medium, the material of the spicules' outer concentric layers is dissolved and silica passes into solution. After 20 to 30 days in alkaline medium, the silica is in excess and precipitates on organic components, forming a network of 300-500-nm thick organosilicon trabeculae, by which the spicules are fused into a single structure. The resulting composite material contains a mineral component of silica and an organic component. The results indicate that the natural organosilicon material can be reformed as a result of self-assembly into three-dimensional or flat structures
Generalized Plasmonic Modelling of the Effect of Refractive Index on Laser-Induced Periodic Nanostructures
Get PDFLaser-induced periodic surface structures (LIPSS) have been studied theoretically employing generalized plasmonic modelling on several dielectric materials such as SiO2, Al2O3, ZnO, AlAs and diamond exposed to 800 nm wavelength multi-pulse femtosecond laser irradiation. The study of the optical properties of the materials during laser irradiation reveals a formation of a metallic like pseudo-material on the irradiated layer during excitation. A study of the grating periodicity of the nanostructures shows that the materials having a high refraction index allow LIPSS formation with a wide range of grating periodicities. Results also show High Spatial Frequency LIPSS formation with periodicities 3 to 8 times lower than the laser wavelength
Tempeh Antioxidant Activity using DPPH Method: Effects of Fermentation, Processing, and Microorganisms
Get PDFTempeh is the main type of traditional Indonesian food that is processed from soybeans fermented by Rhizopus microsporus. This study aims to measure the antioxidant activity of some kind tempeh using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Measurement of antioxidant activity toward tempeh took directly from the producer, tempeh produced on a laboratory scale using Rhizopus spp., Bacillus spp., and Klebsiella sp. K110, tempeh fried and steamed, and tempeh during the fermentation stage. The results showed that the fermentation process soybeans into soybean increase antioxidant activity. The antioxidant activity of tempeh from producers varies between approximately 52-70%. It is because of tempeh fermented at uncontrol conditions so that the microorganisms involved in the fermentation time is also uncontrol. Potential microorganisms vary in determining antioxidant activity. In the group of Rhizopus spp. (ATH 35, ATH 24, ATH 53), it showed that the highest antioxidant activity was found in ATH 35 (84%). In the group of Bacillus spp. the highest antioxidant activity produced by B. megaterium (76%) and higher than the Klebsiella sp. K110 (75%). Thus, the fermented soybeans into tempeh increase antioxidant activity. The existence of the antioxidant activity of tempeh was affected by strains of microorganisms involved during fermentation and processing time that will be consumed
Tribological Behavior Analysis of the ISO 5832-1 Austenitic Stainless-Steel Treated by Optical Fiber Laser Used for Biomedical Applications
Get PDFThe present work analyzed the influence of an optical fiber laser surface treatment process on the tribological behavior of the ISO 5832-1 austenitic stainless-steel, basing on the wear volume and friction coefficient. Specimen of this biomaterial were treated by alternating the laser frequency, in order to find out a condition that improves its tribological resistance. Ball-cratering micro-abrasive wear tests were carried out with a test ball of AISI 316L stainless-steel, used as counter-body, and an abrasive slurry prepared with abrasive particles of black silicon carbide (SiC) and distilled water. The micro-abrasive wear tests results indicated that: i) the hardness of the ISO 5832-1 austenitic stainless-steel increased as a function of the laser frequency, decreasing, consequently, the wear volume, as predicted by Archard's Law; ii) the friction coefficient did not present a proportional behavior with the increase of the optical fiber laser frequency; iii) the best condition to improve the wear resistance of the ISO 5832-1 austenitic stainless-steel was obtained adopting an optical fiber laser frequency of 350 kHz, being reported the lower wear volume
Application of Packed-nanofibers Solid-phase Extraction for Determination of Rhodamine B in Sausage
Get PDFA method for the determination of Rhodamine B in sausage was developed and validated. After extraction of Rhodamine B with acetonitrile from foodstuffs, a novel electrospun polymer nanofibers packed micro-column was used for cleaning and concentrating of the analyte in the sample. High performance liquid chromatography with fluorescence detection (HPLC-Flu) was used for the determination of Rhodamine B in the sample. The mobile phase was composed of 3.0 g L-1 phosphate buffer and methanol (3:7, volume ratio), and the pH was adjusted to 7. 0 with orthophosphoric acid. The results showed that the standard curve was linear over the validated concentrations range of 2-500 ng g-1, and the limit of detection (LOD) and the limit of quantitation (LOQ) for Rhodamine B spiked samples was 0. 2 ng g-1 and 0. 7 ng g-1, respectively. The average recoveries of Rhodamine B were 90.4% -94.3% for sausage, and the relative standard deviation of the method was from 1.7% to 3.8%. This proposed method was applied to real sample, and there was no Rhodamine B found in sausage
A Study of the Intermetallic Compound Growth in Flip-Chip Packages under Thermal Loading
Get PDF The intermetallic compound layers in solder bumps have the brittle feature and can easily fracture under thermal or mechanical loading. Therefore, the intermetallic compound is an issue for the fracture reliability of the solder bumps. In this work, the intermetallic compound growth before and after high temperature storage tests was investigated. The experiment results revealed that the solder bumps with nickel layers could reduce the intermetallic compound growth rate. The nickel layer, which was added in between Cu and SnAg for top solder bumps, was an important factor controlling the intermetallic compound thickness. It was hard to tell the intermetallic compound thickness at time zero; at the time of 147 hours, the intermetallic compound grew to 3.25 µm; at the time of 294 hours, the intermetallic compound grew to 5.25 µm. However, the solder joints were still in good condition
Water Framework Directive and Modelling Using PEGOPERA Simulation Software
Get PDFThe Water Framework Directive 2000/60/EC (WFD) established a framework for community action in the field of water policy. To implement the WFD, the competent authorities for watershed management should use modelling techniques to establish, for example, the pressure/impacts relationship. The PegOpera modelling tool (composed of the water quality model Pegase and a friendly Graphical User Interface), has been developed in order to be compliant with the requirements of the WFD. Pegase is a physicochemical model describing the behaviour of whole river systems, at various scales, from tens to tens of thousands km². The specificity of the model is its ability to work at a high spatial resolution not only for small river basins (water body level), but also for large drainage networks. Already used by several basin management competent authorities, the PegOpera modelling tool proved to be an efficient tool for helping in surface water management from local up to the international district level and is therefore an operational numerical tool for WFD implementation
Physical-Chemical Characteristics of Cutin Separated from Tomato Waste for the Preparation of Bio-lacquers
Get PDFGreen chemistry protocols are proposed to produce high-value chemicals from waste tomatoes. Long-chain hydroxy fatty acids (called cutin acids), in particular the 10,16-dihydroxyhexadecanoic acid and its oligomers, could be innovative building-block chemicals for the synthesis of novel bio-resins and lacquers suitable as internal protective coating for metal food packaging. However, these natural compounds are not currently commercially available. This study investigates the possibility of extracting cutin acids from tomato peels without the use of organic solvents and by an efficient, cost-effective, and environmentally safe method amenable to industrial scale-up. The first route investigated was based on alkaline hydrolysis of the tomato cuticle. The second involved the acid free-selective precipitation of cutin. Finally, cutin was isolated by hydrogen peroxide-assisted hydrolysis. GC-MS analysis revealed the main chemical compound isolated by all methods to be 10,16-dihydroxyhexadecanoic acid, the principal component of tomato cutin, with extraction yields ranging from 81 to 96%. Products are different in terms of appearance, solubility, the degree of crosslinking observed and molecular weight, as shown by GPC analysis. Furthermore, the products extracted were characterized by means of FT-IR spectroscopy and thermal analysis. The cutin obtained through alkaline hydrolysis results the best raw material for bio-resin preparation