Comparative Analysis of the Mechanical Properties of Polymer Matrix Composites Reinforced with Fiberglass Fabric

The composites materials are increasingly displacing the traditional ones and are the most widely used of all groups of engineering materials. Polymer matrix composites have the greatest application and they are used for equipment operating in the sea-water environment and polymer pipes. In this article, the mechanical properties of six types of polymer matrix composites reinforced with fiberglass fabric are considered and analyzed. Two types of resin were used for the matrix – polyester resin and vinyl ester resin. The both types of matrices are reinforced with three different fiberglass fabric- monoaxial, biaxial and triaxial fiberglass. The investigated composites are obtained by mechanical pressing in the form of sixlayer panels. A comparative analysis of tensile strength and banding strength of the six types investigated composites was made. A macrofractographic analysis of the structure was also performed.

High-yield synthesis of silver nanowires for transparent conducting PET films

Silver nanowires (AgNWs) with ultrahigh purity and high yield were successfully synthesized by employing a modified facile polyol method using PVP as a capping and stabilizing agent. The reaction was carried out at a moderate temperature of 160 °C under mild stirring for about 3 h. The prepared AgNWs exhibited parallel alignment on a large scale and were characterized by UV–vis spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and PL spectroscopy. The luminescent AgNWs exhibited red emission, which was accredited to deep holes. The SEM results confirmed the formation of AgNWs of 3.3 to 4.7 µm in length with an average diameter of about 86 nm, that is, the aspect ratio values of the AgNWs exceeded 45. An ink consisting of hydroxyethyl cellulose (HEC) and AgNWs was transferred to polyethylene terephthalate (PET) films by simple mechanical pressing. The PET films retained transparency and flexibility after the ink coating. The maximum transmittance value of as-prepared PET films in the visible region was estimated to be about 92.5% with a sheet resistance value of ca. 20 Ω/sq. This makes the films a potential substitute to commonly used expensive indium tin oxide (ITO) in the field of flexible optoelectronics.

UV Inscription and Pressure Induced Long-Period Gratings through 3D Printed Amplitude Masks

In this work, we demonstrate for the first time the capability to inscribe long-period gratings (LPGs) with UV radiation using simple and low cost amplitude masks fabricated with a consumer grade 3D printer. The spectrum obtained for a grating with 690 µm period and 38 mm length presented good quality, showing sharp resonances (i.e., 3 dB bandwidth < 3 nm), low out-of-band loss (~0.2 dB), and dip losses up to 18 dB. Furthermore, the capability to select the resonance wavelength has been demonstrated using different amplitude mask periods. The customization of the masks makes it possible to fabricate gratings with complex structures. Additionally, the simplicity in 3D printing an amplitude mask solves the problem of the lack of amplitude masks on the market and avoids the use of high resolution motorized stages, as is the case of the point-by-point technique. Finally, the 3D printed masks were also used to induce LPGs using the mechanical pressing method. Due to the better resolution of these masks compared to ones described on the state of the art, we were able to induce gratings with higher quality, such as low out-of-band loss (0.6 dB), reduced spectral ripples, and narrow bandwidths (~3 nm).

Quality attributes of roasted Arabica coffee oil extracted by pressing: composition, antioxidant activity, sun protection factor and other physical and chemical parameters

This research reports a comprehensive characterization of the composition profile and physical and chemical characteristics of roasted Arabica coffee oil obtained by mechanical pressing. The oil presented a peroxide value of 3.21 meq·kg-1 and an acid value of 7.3 mg KOH·g-1. A higher proportion of unsaturated fatty acids (58%), predominantly linoleic (L) and palmitic (P) acids, was observed; PLL and PLP were estimated as the main triacylglycerols. The oil was characterized by high contents in diterpenes and tocopherols (3720 and 913 mg·100g-1, respectively), the presence of caffeine and chlorogenic acids, as well as a high sun protection factor (9.7) and ABTS free radical-scavenging capacity (12.5 mg Trolox·mL-1). Among the 35 volatile compounds studied, furfurythiol and pyrazines were the main components of the oil. These properties showed that roasted coffee oil has good potential for use in food and cosmetics.

Flaxseed oil: Extraction, health benefits and products

Flaxseed is rich in ?-linolenic acid (ALA), lignans, proteins and dietary fibers, which has been considered as an important food ingredient. As one of most functional ingredients in flaxseed, flaxseed oil could provide many potential health benefits, such as cardiovascular protection, anti-tumor, anti-inflammatory, live protection, diabetes treatment, etc. Besides mechanical pressing and solvent extraction for flaxseed oil, various new extraction processes, for example, microwave-assisted extraction, supercritical CO2 extraction, subcritical extraction, three-phase partitioning, enzyme-assisted three-phase partitioning, etc., have been investigated. Currently, flaxseed oil has been incorporated into some regular food formulations including liquid or solid powder drink, meat products, baking foods, etc. However, due to high ALA in flaxseed oil, it is a great challenge for the development of flaxseed-oil based products. In present paper, the latest development of the extraction of flaxseed oil, the potential benefits of flaxseed oil, and flaxseed oil-based foods, were reviewed. Regarding the studies of flaxseed oil in our group was also highlighted.

Uji Kinerja Screw Oil Press Machine Ditinjau dari Rendemen dan Kualitas Minyak Kelapa yang Dihasilkan

ABSTRAK Minyak kelapa merupakan salah satu produk utama dari pengolahan daging kelapa melalui proses ekstraksi kering dan basah. Minyak kelapa dapat diproduksi melalui ekstraksi kering kopra mentah dengan perolehan minyak 63-65%, dan salah satu metodenya adalah dengan cara pengepresan mekanis menggunakan Mesin Screw Press Oil. Pada proses pengepresan, ada banyak faktor yang menyebabkan kehilangan minyak sehingga perolehan produk minyak menjadi lebih sedikit. Pada penelitian ini ditujukan untuk diperolehnya hasil minyak kelapa maksimum dengan mengamati faktor kondisi operasi selama proses pengepresan, seperti kecepatan putar sekrup dan temperatur. Selanjutnya, diperoleh juga jumlah intensitas konsumsi energi dan efisiensi menekan dalam proses produksi minyak kelapa dari bahan baku kopra menggunakan Mesin Screw Press Oil. Metode penelitian dimulai dengan tahap persiapan bahan dan tahap pengujian mesin dengan menganalisis intensitas energi dan efisiensi pengepresan pada Mesin Pengepres Minyak Sekrup yang dibutuhkan dalam proses pengepresan minyak kelapa dari kopra dalam hal hasil minyak kelapa yang dihasilkan. Kata kunci: Mesin press minyak screw, kopra, minyak kelapa. ABSTRACTCoconut oil is one of the main products from processing coconut meat through dry and wet extraction. In dry extraction, coconut oil is produced with raw copra material which has an oil content of 63-65%. The production process of coconut oil from copra is done by mechanical pressing using a Screw Press Oil Machine. In the pressing process, there are many factors that cause oil losses so that the acquisition of oil products becomes less. Therefore, this study aims to obtain maximum coconut oil yield by analyzing several factors of operating conditions during the pressing process such as screw rotational speed and temperature. Furthermor, it is also obtained the amount of energy consumption intensity and pressing efficiency in the production process of coconut oil from copra raw materials using the Screw Press Oil Machine. The research method begins with the preparation stage of the material and the engine testing stage by analyzing the energy intensity and pressing efficiency at the Screw Oil Press Machine needed in the process of pressing coconut oil from copra in terms of the yield of coconut oil produced. Keywords: Screw oil press machine, copra, coconut oil.

Valorization of argan oil: all you need to know about argan oil from Morocco

This work makes it possible to study the argan oil which has extracted by several extraction methods (artisanal, mechanical pressing of roasted almonds, mechanical pressing of unroasted almonds, solvent extraction, pulped by a goat), after extraction, a detailed Physico-chemical study was done on this oil to certify its quality, the study of this work makes it possible to achieve an official standard for argan oil and studies the influence of the extraction method and the origin of production on the chemical composition. The study shows that roasting appears as a parameter influencing the acidity value of argan oil. Analysis of the peroxide index shows that the samples of argan oil extracted by the artisanal method and that those pulped by goats have a higher peroxide content. The sterol composition as per the data in the literature. They are essentially Δ-7-stigmasterols. The main products are schottenol and spinasterol. The composition of fatty acids and sterols shows no significant variation. These results are consistent with those reported in the literature. This shows that the origin and the method of extraction do not influence the nutritional qualities of argan oil. The results for the tocopherols show that the extraction method (plump by a goat) and roasting can influence the composition of the tocopherols. On the other hand, the sample obtained by the artisanal method has a lower content of total tocopherols. Roasting decreases the total content of α-tocopherol. After this study, it is urgent to ensure the quality of this oil, so Physico-chemical analyzes were carried out to detect fraud in pure argan oil. Finally, we determined the influence of the fruit form of the argan tree (spindle-shaped, apiculate, oval, spherical) on the Physico-chemical parameters of argan oil.

Highly Ordered Arrays of Silver Nanowires for Transparent Conducting PET Film

Silver nanowires (AgNWs) with ultra-high purity and high yield are successfully synthesized by employing a modified facile polyol method using PVP as capping and stabilizing agent. The reaction is carried out at a moderate temperature of 140 °C and mild stirring rate for about 3 hours. The prepared AgNWs are characterized by UV-Vis spectroscopy, scanning electron microscopy (SEM), X-rays diffraction (XRD) and PL spectroscopy. The luminescent AgNWs exhibit red emission which is accredited to the deep holes. The SEM results confirm the formation of AgNWs of length ranging from 35 to 40 µm and an average diameter of about 86 nm, thus their aspect ratios exceed 400. The AgNWs and hydroxyethyl cellulose (HEC) based ink is transferred to polyethylene terephthalate (PET) film by simple mechanical pressing. The PET film has retained its transparency and flexibility after AgNWs ink coating. The % transmittance of as-prepared PET film is estimated to be about 92.5% with a lower sheet resistance value ~ 20 Ω, which can make it a potential substitute to commonly used expensive indium tin oxide (ITO) films in the field of optoelectronics.