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Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The main aspects of strengthening aluminium alloys with zirconium are considered in detail in this work. As established, the improvement of the mechanical properties of aluminium alloys with zirconium occurs not only due to the grinding of the grains of the solution of the main alloying component in aluminium, but also by the refining effect of zirconium that is purifying the aluminium alloys from hydrogen. In addition, the strengthening of aluminium alloys with zirconium is achieved by preventing the appearance of undesirable brittle phases, for example, Mg2Al3, Mg5Al8, in alloys of the Al- Mg system that is achieved by the injection of zirconium. [ABSTRACT FROM AUTHOR]

A highly transparent sole rubber was prepared by cis-butadiene rubber and dissolved polystyrene-butadiene rubber as the materials, fumed silica as the reinforcing agent, coupling agent and vulcanizing agent. The effects of coupling agent types and fumed silica on the rubber properties were studied. The results show that the optimal conditions for the preparation of highly transparent sole rubber are to choose a mixture of BH-8172 with different molecular weights of vinyl modified silane as the coupling agent, and 20 phr of gas-phase silica HL-200 as the reinforcing agent, whose light transmittance is 80.7%, the tensile strength is 11.0 MPa, the elongation at break is 433%, the hardness of Shore is 68A, and the relative wear volume is 98mm³. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: This paper presents a comprehensive review of nanocellulose and its application in several applications, including composites, biomedical, and food packaging fields. Design/methodology/approach: General explanations about cellulose and nanocellulose have been described. Different types of nanocellulose (cellulose nanofibers, cellulose nanocrystals, bacterial nanocellulose) as well as their isolation processes (mechanical process, chemical process) have been reviewed. Several surface modifications have been explained to improve the dispersion of nanocellulose in non-polar polymers. The possible utilization of nanocellulose in composites, biomedical, and food packaging fields have also been analysed. Findings: This review presents three application fields at once, namely composites, biomedical, and food packaging fields. In the composite field, nanocellulose can be used as a reinforcing agent which increases the mehcnical properties such as tensile strength and toughness, and thermal stability of the final composites. In the biomedical field, nanocellulose is reinforced into hydrogel or composites which will be produced as tissue scaffolding, wound dressing, etc. It is found that the addition of nanocellulose can extend and control the drug release. While in the packaging field, nanocellulose is added into a biopolymer to improve the barrier properties and decrease the water and oxygen vapor transmission rates. Research limitations/implications: Nanocellulose has a hydrophilic nature, thus making it agglomerated and difficult to disperse in most non-polar polymers. Therefore, certain surface modification of nanocellulose are required prior to the preparation of composites or hydrogels. Practical implications: Further research regarding the toxicity of nanocellulose needs to be investigated, especially when applying it in the biomedical and food packaging fields. Originality/value: This review presents three application fields at once, namely composites, biomedical, and food packaging fields. [ABSTRACT FROM AUTHOR]

Point-Q reinforcing agent, recycled glass material, calcium carbonate powder and styrene-acrylic emulsion are used in the ternary cementitious material system to modify and strengthen the polymer cement waterproof mortar. The experimental results show that when the proportion of added Sulphoaluminate cement, the addition of reinforcing agent, the cement-sand ratio, the mass ratio of emulsion to powder and the ambient temperature are at values of 26%,1.0%,1:1,1:3 and 0-40 111,the strength, viscosity, setting time and impermeable pressure of the new polymer modified waterproof mortar reach a higher level than before, filling that defects of poor adhesion and low strength caused by the smooth surface of the recycled glass material when it's used in the waterproof mortar. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Modification of cellulose fibers is a promissory alternative for the production of new composite materials, but the high hydrophilicity of cellulose limits its use as a reinforcing agent in the making of olefin-based composites. The aim of this research was to develop reinforcing agents based on cellulose fibers modified by insertion of end-alkyl groups from pyrolytic bio-oil (PBO). For that, PBO of sugarcane bagasse was obtained and characterized by several techniques including gas chromatography coupled to mass spectrometry. Later, the surface of cellulose fibers was activated using methylene-bis-isocyanate and modified using acetic acid, formic acid, and PBO. Results show that the modification of cellulose surface is possible by the use of PBO at low temperature obtaining results like to those obtained when organic acids are used. [ABSTRACT FROM AUTHOR]

The brittleness of ethyl cellulose (EC) film limited its full applications, and the addition of plasticizers is one of the most common methods to reduce its brittleness. However, the mechanical properties are normally dropped with the addition of plasticizers. Herein, cellulose nanocrystal (CNC) was chosen as a reinforcing agent to improve its mechanical properties. CNC was firstly extracted from the tobacco-stem and then modified by epoxidized soybean oil (ESO) via ring-opening grafting to obtain epoxidized soybean oil grafting CNC (ECNC). The grafting effect was evaluated by FTIR and XPS. After that, the films of ECNC/EC nanocomposites were prepared by the solution-casting method, and their mechanical, thermal and optical properties and fracture morphology were investigated. The results showed that at 4 phr loading of ECNC, the tensile strength of the nanocomposite film was up to 43.7 Mpa (about twice as much as that of the EC film plasticized by ESO), and the elongation at break was not influenced. Moreover, a higher thermal decomposition temperature was achieved for the ECNC/EC films. Besides, owing to the good dispersion, ECNC had no significant impact on the transparency, and the films presented high light transmittance in the visible light region. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad de Ingeniería Universidad de Antioquia is the property of Universidad de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of sulfated (original), carboxylated (oxidized), and Jeffamines M2005‐grafted cellulose nanocrystals (CNCs) on the barrier and mechanical properties of thermoplastic starch (TPS) and poly(3‐hydroxybutyrate) (P(3HB)) matrices was investigated. CNCs were first oxidized via a catalytic reaction using NaClO as an oxidant and then grafted with an amine‐terminated ethylene oxide (EO)/propylene oxide (PO) copolymer (Jeffamine) by an amine‐acid coupling reaction. A degree of oxidation (DO) of 0.108 (mol/mol of anhydroglucose) was attempted for the carboxylated CNCs, whereas a degree of substitution (DS) of 0.04 (mol/mol of anhydroglucose) was determined for the M2005‐grafted CNCs. These values indicated satisfactory reactive process, with yields of 68% and 47.3% for the carboxylation and peptide coupling reactions, respectively. Fourier‐transform infrared spectroscopy (FTIR) analysis showed bands at 1643 cm−1 and 1550 cm−1 in the spectrum of M2005‐grafted CNCs, which qualitatively indicated the amide bond formation. In addition, the morphology and the zeta potential of modified CNCs ensured their homogeneity, stability, and surface degree of charge. In spite of a decrease in the solubility in water of the modified crystals, the procedure of chemical modification used avoided any variation in their crystalline structure and thermal stability. Then, the incorporation of sulfated, oxidized, or M2005‐grafted CNCs in matrices of TPS and P(3HB) allowed to produce reinforced nanocomposite films, with excellent barrier properties. Therefore, the chemical compatibility between CNCs and the polymer matrices is essential to produce attractive nanocomposites with improved mechanical properties for industrial applications. [ABSTRACT FROM AUTHOR]

The paper studies the behavior of ceramic porous tungsten alloy with reinforcing agents under the shock-wave loading conditions. Penetrating capacity of tungsten kinetic energy projectiles is calculated and experimentally investigated during their high-speed impacts on steel plates. It is shown that the increased penetration depth of tungsten projectiles exceeds that of the prototype with relevant weight and size, made of tungsten-nickel-iron cast alloy. A mathematical model is developed together with the design technique of the behavior of tungstennickel-iron-cobalt metal foams alloyed with boron carbide, tungsten titanium carbide and tungsten carbide during the high-speed impact interaction. The composite ceramic material is described here as a porous medium. The matrix of this medium is a homogeneous two-phase mixture of the tungsten-nickel-iron-cobalt system and reinforcing agents added in the required proportions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate a popular reinforcing agent in the papermaking industry through a quick, environmentally friendly, microwave-assisted method. The preparation and characterization of cellulose-CaCO3 composites through this route, in a mixed solution of an ionic liquid and ethylene glycol, can occur within a 10-min timeframe. The chemical compounds, calcium acetate and sodium carbonate, were used as reactants for the as-obtained CaCO3 crystals. A NaOH-urea aqueous solution was used to treat the cellulose and prepare cellulose- CaCO3 composites. It was discovered that the addition of ionic liquids favors the preparation of cellulose-CaCO3 composites. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of binder component on the creep properties of polymer-bonded explosive (PBX), three-point bending creep behaviors of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)-based PBX and its styrene copolymer modified formulation were studied by dynamic mechanical analyzer. The experimental results showed that owing to the addition of reinforcing agent (styrene copolymer) with high glass transition temperature and high mechanical strength, the creep resistance performance of the modified formulation was improved with reduced creep strain and constant creep rate and prolonged creep failure time. A six-element mechanical model was applied to simulate the creep behaviors of TATB-based PBX and its modified formulation. The constitutive equation of creep curves under different conditions were obtained by nonlinear fit. The predicted theoretical results coincided quite well with the experimental data. [ABSTRACT FROM AUTHOR]

At ambient atmospheric condition copper nanoparticles (CuNPs) were prepared in aqueous medium using copper chloride, sodium borohydride, ascorbic acid and polyvinyl alcohol (PVA) of two different molecular weights ( Ms). The physical appearance of the prepared sol of CuNPs has been found to be stable for a couple of weeks when kept in ambient atmospheric condition, as confirmed by ultraviolet-visible absorption spectroscopy. Transmission electron microscopy exhibits spherical morphology of CuNPs with an average size of 3.5 ± 1.1 nm developed in the sol, where PVA of high M renders smaller size (2.5 nm) than that of low M. The synthesised CuNPs were embedded in palm oil fibres (POFs) via cationisation process. The cationisation of POF was ascertained by Fourier-transformed infrared and zero point charge determination. The inclusion of nanoparticles (NPs) onto the fibres' surface has been consistently proven by Fourier transformed infrared spectroscopy, X-ray diffraction study, field emission scanning electron microscopy, energy dispersive X-ray study and thermogravimetric analysis. CuNP-coated POF showed the increment of tensile strength (∼34 %) and antifungal activity (24 %) with respect to control fibres. The observed findings suggest that NPs can be effectively used as reinforcing agents in natural fibres to improve their property and durability. [ABSTRACT FROM AUTHOR]

For preventing and extinguishing the spontaneous combustion of coal seam, based on the importance for sealing air leakage channels in roadway, developed a material of light-paste for coalmine, and research its ingredient, proportion and performance. The result indicates that the component ratio of the material is which PB exciting agent is 20%, complex reinforcing agent is 2%, complex expansion agent is 1%, and A-material is 77%. The performances of compressive strength, swelling ratio and expansion time are optimum. The light-paste material can effectively seal air leakage channels for preventing and extinguishing the spontaneous combustion of coal seam in coalmine. [ABSTRACT FROM AUTHOR]

In this study the feasibility of applying two kinds of mudar (Calotropis gigantea) fibers, namely bark fibers and seed fibers, as an alternative raw material for fiber-reinforced composite (FRC) is investigated. The chemical analysis of the bark and seed fibers indicates that their main components are holocellulose 76 and 69%, cellulose 57 and 49%, lignin 18 and 23%, and alkali soluble substances 17 and 15%, respectively. There are statistically significant differences in the bark and seed fiber dimensions. The bark fibers are long, with a thin wall relative to their diameter, and are therefore lightweight. The seed and bark fibers are very similar to hard- and soft-woods, in terms of chemical compositions and fiber dimensions, respectively. The mechanical properties of the mudar bark fibers are: tensile strength 381 MPa, strain at break 2.1% and Young's modulus 9.7 GPa. In general, both types of fibers have enough potential for replacing or supplementing other fibrous raw materials as reinforcing agent. [ABSTRACT FROM AUTHOR]

In this work, poly(lactic acid) (PLA)/gelatin/PLA multilayer films supplemented with cellulose nanocrystals and antioxidant extract from almond shell (AS) by-products were developed by solvent casting technique for active food packaging. The almond shell antioxidant extract (ASE) was obtained by microwave-assisted extraction, while cellulose nanocrystals (CNCs) were extracted from AS by a sequential process of alkalization, acetylation and acid hydrolysis. Four formulations were obtained by adding 0 (control), 6 wt.% of ASE (FG/ASE), 4.5 wt.% of CNCs (FG/CNC) and 6 wt.% + 4.5 wt.% of ASE + CNCs, respectively, (FG/ASE + CNC) into fish gelatin (FG). PLA/FG/PLA multilayer films were prepared by stacking two outer PLA layers into a middle FG film. A surface modification of PLA by air atmospheric plasma treatment was optimized before multilayer development to improve PLA adhesion. Complete characterization of the multilayers underlined the FG/ASE + CNC formulation as a promising active reinforced packaging system for food preservation, with low values of transparency, lightness and whiteness index. A good adhesion and homogeneity of the multilayer system was obtained by SEM, and they also demonstrated low oxygen permeability (40.87 ± 5.20 cm3 mm m−2 day) and solubility (39.19 ± 0.16%) values, while mechanical properties were comparable with commercial plastic films. The developed multilayer films were applied to Hass avocado preservation. The initial degradation temperature (Tini), DSC parameters and in vitro antioxidant capacity of the films were in accordance with the low peroxide and anisidine values obtained from avocado pulp after packaging for 14 days at 4 °C. The developed PLA/FG/PLA films supplemented with 6 wt.% ASE+ 4.5 wt.% CNCs may be potential bioactive packaging systems for fat food preservation. [ABSTRACT FROM AUTHOR]

The usage of edible coatings (ECs) represents an emerging approach for extending the shelf life of highly perishable foods, such as fresh and fresh-cut fruits and vegetables. This review addresses, in particular, the use of reinforcing agents in film-forming solutions to tailor the physicochemical, mechanical and antimicrobial properties of composite coatings. In this scenario, this review summarizes the available data on the various forms of nanocellulose (NC) typically used in ECs, focusing on the impact of their origin and chemical or physical treatments on their structural properties (morphology and shape, dimension and crystallinity) and their functionality. Moreover, this review also describes the deposition techniques of composite ECs, with details on the food engineering principles in the application methods and formulation optimization. The critical analysis of the recent advances in NC-based ECs contributes to a better understanding of the impact of the incorporation of complex nanoparticles in polymeric matrices on the enhancement of coating properties, as well as on the increase of shelf life and the quality of fruits and vegetables. [ABSTRACT FROM AUTHOR]

In this paper, the flexural modulus and wear resistance of silicon carbide and alumina whisker-reinforced epoxy composites are reported. The composites were fab ricated from epoxy resins and whiskers which were produced in a plasma furnace. The resulting silicon carbide and alumina whisker-reinforced epoxy composites have low den sities, high flexural moduli and good wear resistance. The specific stiffnesses of these two composites with 16-18% weight fraction of whiskers were 1.59 and 1.50 (GPa/g/mm3) respectively. These values were 46 and 37 percent higher than that of the unreinforced epoxy resins. The silicon carbide and alumina whiskers which have low densities, high strength, high length to diameter ratios, and large surface area, are effective reinforcing agents for epoxy composites. Also, the factors that determine the flexural modulus of the composite are discussed. [ABSTRACT FROM PUBLISHER]

More than 10 million tons of textile waste are disposed through landfill every year in North America. The disposal of textile waste via landfill or incineration causes environmental problems and represents a waste of useful resources. In this work, we explored the possibility to directly extract cellulose nanocrystals (CNCs) from untreated textile waste through two methods, namely sulfuric acid hydrolysis and three-step oxidization. CNCs with cellulose Iβ crystalline structure and rod-like shape were successfully obtained. The aspect ratios of CNCs prepared from acid hydrolysis and oxidization were 10.00 ± 3.39 and 17.10 ± 12.85, respectively. Their application as reinforcing agent of soybean protein isolate (SPI) film was evaluated. With the addition of 20% CNCs, the composite film maintained the high transparency, while their water vapor barrier property, tensile strength, and Young's modulus were significantly improved. This research demonstrates a promising approach to recycle textile waste, and more value-added applications based on the derived CNCs could be expected. [ABSTRACT FROM AUTHOR]

Potassium hexatitanate (PHT) with chemical formula K2Ti6O13 has a tunnel structure formed by TiO2 octahedra sharing edges or corners and with the potassium atoms located in the tunnels. This material has attracted great interest in the areas of photocatalysis, reinforcement of materials, biomaterials, etc. This work summarizes a large number of studies about methods to prepare PHT since particle size can be modified from millimeter to nanometric scale according to the applied method. Likewise, the synthesis method has influenced the material properties as band-gap and the final mechanical performance of composites when the reinforcement is PHT. The knowing of synthesis, properties and applications of PHT is worthwhile for the design of new materials and for the development of new applications taking advantage of their inherent properties. [ABSTRACT FROM AUTHOR]