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Polyether-ether-ketone (PEEK) exhibits great potential in being a replacement for metal components across various applications relying on the mechanical and tribological properties. However, there is still much to be done to improve its properties. The main motivation of this paper is to improve the tribological and mechanical properties of PEEK simultaneously for more severe working environment. Therefore, dialkyl pentasulfide (RC2540) was proposed to fill into the cavity of CNTs to prepare nano-capsules, which were then filled into PEEK to prepare PEEK/nano-capsules composites. The existence of nano-capsules in PEEK was analyzed, and the friction and wear properties exhibited by PEEK composites against GCr15 steel were examined using pin-disk friction pairs, and the self-lubricating mechanism of PEEK composites in friction was revealed. Findings of this study indicated that when the mass fraction of nano-capsules was less than 5%, the filling of nano-capsules could improve the tensile strength of PEEK and reduced the friction coefficient and specific wear rate of PEEK by filling nano-capsules. During the friction process, RC2540 in the nano-capsules can be released as PEEK wears so that a self-lubricating layer can be formed for reducing PEEK composites' friction and wear. [ABSTRACT FROM AUTHOR]

Grinding fluid often struggles to enter the grinding area and overcoming this challenge has been a major focus of research in recent years. Therefore, CNTs@T304 nano-capsules are prepared by filling the cavities of CNTs with a lubricant of T304. CNTs@T304 nano-capsules were used as an additive in this paper to prepare resin grinding wheels and nanofluids, respectively. The resin wheels filled with nano-capsules were used for grinding under the lubrication of nanofluids, and T304 could then be released to the grinding area to play a self-lubricating role during grinding. First, CNTs@T304 nano-capsules were characterized, and the properties of the prepared grinding wheels and nanofluids were tested. Second, the effects of the filling of nano-capsules and grinding speed on the grinding force, grinding temperature, surface roughness, and grinding ratio were studied. Finally, the lubrication mechanism of the nano-capsules was revealed through surface analysis of the workpiece. The results suggested that nano-capsules had good thermal stability and the nanofluid prepared from them exhibited good dispersion stability and thermal conductivity. The grinding wheel was found to satisfy the service conditions when the filling content was less than 15%. Compared with a common wheel, the grinding force and grinding temperature were reduced by 24% and 28%, respectively, and the surface roughness of the workpiece and the grinding ratio were increased by 18% and by 21%, respectively, when grinding GCr15 steel with the nano-capsule wheel. Lubrication with nanofluids could further reduce the grinding force, grinding temperature, and surface roughness values. During grinding, the self-lubrication film formed by the T304 released from the nano-capsules in the wheel served first and foremost as a lubricant. The intervention of the nanofluid enhanced the heat-exchange effect and lubrication efficiency in the grinding zone. [ABSTRACT FROM AUTHOR]

Polyether-ether-ketone (PEEK) exhibits great potential in being a replacement for metal components across various applications relying on the mechanical and tribological properties. However, there is still much to be done to improve its properties. The main motivation of this paper is to improve the tribological and mechanical properties of PEEK simultaneously for more severe working environment. Therefore, dialkyl pentasulfide (RC2540) was proposed to fill into the cavity of CNTs to prepare nano-capsules, which were then filled into PEEK to prepare PEEK/nano-capsules composites. The existence of nano-capsules in PEEK was analyzed, and the friction and wear properties exhibited by PEEK composites against GCr15 steel were examined using pin-disk friction pairs, and the self-lubricating mechanism of PEEK composites in friction was revealed. Findings of this study indicated that when the mass fraction of nano-capsules was less than 5%, the filling of nano-capsules could improve the tensile strength of PEEK and reduced the friction coefficient and specific wear rate of PEEK by filling nano-capsules. During the friction process, RC2540 in the nano-capsules can be released as PEEK wears so that a self-lubricating layer can be formed for reducing PEEK composites’ friction and wear.

Grinding fluid often struggles to enter the grinding area and overcoming this challenge has been a major focus of research in recent years. Therefore, CNTs@T304 nano-capsules are prepared by filling the cavities of CNTs with a lubricant of T304. CNTs@T304 nano-capsules were used as an additive in this paper to prepare resin grinding wheels and nanofluids, respectively. The resin wheels filled with nano-capsules were used for grinding under the lubrication of nanofluids, and T304 could then be released to the grinding area to play a self-lubricating role during grinding. First, CNTs@T304 nano-capsules were characterized, and the properties of the prepared grinding wheels and nanofluids were tested. Second, the effects of the filling of nano-capsules and grinding speed on the grinding force, grinding temperature, surface roughness, and grinding ratio were studied. Finally, the lubrication mechanism of the nano-capsules was revealed through surface analysis of the workpiece. The results suggested that nano-capsules had good thermal stability and the nanofluid prepared from them exhibited good dispersion stability and thermal conductivity. The grinding wheel was found to satisfy the service conditions when the filling content was less than 15%. Compared with a common wheel, the grinding force and grinding temperature were reduced by 24% and 28%, respectively, and the surface roughness of the workpiece and the grinding ratio were increased by 18% and by 21%, respectively, when grinding GCr15 steel with the nano-capsule wheel. Lubrication with nanofluids could further reduce the grinding force, grinding temperature, and surface roughness values. During grinding, the self-lubrication film formed by the T304 released from the nano-capsules in the wheel served first and foremost as a lubricant. The intervention of the nanofluid enhanced the heat-exchange effect and lubrication efficiency in the grinding zone.

The aim of this study was to optimize the nanoencapsulation of fish Omega 3 fatty acids with use of complex coasevation technique which was performed by using response surface methodology (RSM) in the central composite design (CCD). Nanoparticles containing omega-3 fatty acid were produced by Rainbow trout skin gelatin and Arabic gum as walls using complex coacervation technique. The effects of three independent variables as fish gelatin concentration (33-66%), the concentration of omega-3 fatty acids (10-30%) and the homogenizer speed at three levels (10000, 15000 and 20000 rpm) on the dependent variables such as particle size, oil level, encapsulated oil and nanoencapsulation efficiency were evaluated. The results showed that the homogenizer speed significantly had the greatest impact on the particle size (P

Abstract Background: Ferula assa-foetida is one of the common medicines that was used as antiseptic with a view to traditional uses, it can be used as a safe and effective drug to treat diseases particularly resistant bacterial infections. This study aims to product gelatin nano- capsules containing Ferula assa-foetida essential oil and investigate their antioxidant and antibacterial activities. Materials and Methods: This experimental study was performed on gelatin nano-capsules containing Ferula assa-foetida essential oil (FAO) (2, 4, 6 and 8% w/w), glycerol (25% w/w) as plasticizer and glutaraldehyde as cross-linker. The morphology, antioxidant and antibacterial activities and operation of the nano-capsules were assessed according to American Standards by Scanning Electron Microscopy, ABTS, and microbiological tests. Results: Gelatin nano-capsules exhibited low antioxidant and antibacterial activities while gelatin nano-capsules incorporated with FAO exhibited excellent antioxidant and antibacterial. The highest rates of these effects were seen merged with 8% of FAO. Conclusion: Gelatin nano-capsules merged with FAO have excellent physical form, as well as they are an appropriate antioxidant and antibacterial that have been considered to produce antoxidant and antibacterial drugs.

Objective: The main purpose of the current study was to determine the effect of nano-capsules containing risedronate on calvarial bone formation in rabbit. Materials and Methods: Fifteen adult rabbits were allocated to the study. Four holes were created in the calvarial bone. Holes 1-4 were filled as described below: hole 1 was right unfilled and kept as control; hole 2 was filled with nano bone; hole 3 was filled using an autogenous bone; and hole 4 was filled with a mixture of nano-capsules containing risedronate. At 4, 8 and 12 weeks after surgery, blood samples were obtained and red blood cell, white blood cell, hemoglobin, hematocrit, mean cell volume, mean cell HGB and platelet counts were determined. Then animals were scarified and bone density was determined using radiography images. Results: Bone formation in nano risedronate + autograft and autograft were 0.31 ± 0.03 and 0.25 ± 0.02, respectively, while in nano risedronate and control groups were 0.11 ± 0.01 and 0.08 ± 0.02, respectively (P < 0.05). Significant differences were observed in bone density in nano risedronate + autograft as 0.37 ± 0.01, while the density in the autograft, nano risedronate, and control groups were as 0.32 ± 0.01, 0.14 ± 0.01, and 0.09 ± 0.02, respectively (P < 0.05). Bone density after 12 weeks were 0.51 ± 0.01, 0.36 ± 0.02, 0.21±0.01, and 0.19 ± 0.02 in nano risedronate + autograft, nano risedronate, autograft, and control groups, respectively (P < 0.05). In all stages of the study, the nano risedronate + autograft group had better bone formation in comparison to the other groups (P < 0.05). Different filling materials of defects had no effect on blood hematology indexes (P > 0.05). Conclusion: These results suggest nano risedronate + autograft has positive effects on calvarial bone defects healing in rabbit. [ABSTRACT FROM AUTHOR]

Ionic liquids can serve as an environmentally-friendly replacement for solvents in emulsions, therefore they are considered suitable to be used as an emulsified medium for various active materials one of which are extractors of metal ions. Increasing the extraction efficiency is considered to be one of the key objectives when working with such extraction systems. One way to improve the extraction efficiency is to increase the contact area between the extractant and the working ionic solution. This can be accomplished by creating a nano-emulsion of ionic liquid containing such an extractant. Since emulsification of ionic liquid is not always possible in the sample itself, there is a necessity of creating a stable emulsion that can be added externally and on demand to samples from which metal ions need to be extracted. We propose a method of fabrication of a highly-stable extractant-loaded ionic liquid-in-water nano-emulsion via a low-energy phase reversal emulsification followed by continuous layer-by-layer polyelectrolyte deposition process to encapsulate the nano-emulsion and enhance the emulsion stability. Such a multilayered stabilized nano-emulsion was tested for extraction of Cd 2+ and Ca 2+ ions in order to determine its extraction efficiency and selectivity. It was found to be effective in the extraction of Cd 2+ ions with near 100% cadmium removal, as well as being selective since no Ca 2+ ions were extracted. The encapsulated emulsion was removed from samples post-extraction using two methods – filtration and magnetic separation, both of which were shown to be viable under different circumstances – larger and mechanically stronger capsules could be removed by filtration, however magnetic separation worked better for both smaller and bigger capsules. The long-term stability of nano-emulsion was also tested being a very important characteristic for its proposed use: it was found to be highly stable after four months of storage time. [ABSTRACT FROM AUTHOR]

In this study, nano-capsules of lansiumamide B (NCLB) was prepared by the microemulsion polymerization method to improve the nematicidal efficacy of lansiumamide B (LB). An optimal formulation was gained by orthogonal experiment design based on the encapsulation efficiency (En, %) value. The optimized NCLB were spherical and uniform under transmission electron microscopy (TEM). The mean particle size, zeta potential and En were (38.50±0.64) nm, (−70.5±0.76) mV and (95.13±1.16)%, respectively. The release profile indicated that the accumulated release of LB in NCLB reached up to 82% within 96 h. Effects of NCLB against Bursaphelenehus xylophilus and J2 of Meloidogyne incognita were reported in this paper. The nematicidal activity of NCLB has been remarkably increased, with LC50 values of 2.1407 mg L−1 and 19.3608 mg L−1, respectively, at 24 h after treatment. The disease progression and the average number of root knots of Ipomoea aquatica were 1.50 and 7.25, respectively, in the treatment of NCLB, at concentration of 200 mg L−1, significantly lower than the treatment of LB and ethoprophos. Compared to control, the treatments of NCLB, LB and ethoprophos leaded the disease progression to drop 68.42, 36.84 and 26.32%, respectively, and caused the average number of root knots to fall 83.94, 78.03 and 63.66%. These results suggested that NCLB, as a novel nematicides formulation, performed more efficient and longer effective maintenance against plant parasitic nematodes.

In the present work, carotenoids were isolated (1.2%) from crude palm oil and encapsulated with isabgol fiber (Psyllium husk). The efficiency of encapsulation was 82.23±1.42%. The morphology of the capsules showed rough surface texture with minimal pores. The amorphous natures of the nano-capsules was obvious from X-ray diffraction patterns. DSC studies showed high thermal stability of the nano-capsules between 20–120 °C. In vitro release studies revealed that controlled release from the nano-capsules could be achieved using isabgol fiber as encapsulant. However it was observed that the nano-capsules followed a non-Fickian diffusion pattern. Good DPPH-radical scavenging and metal-chelation activities were observed for encapsulated carotenoids. Shelf-life studies showed that the nano-capsules gradually degraded at 97% relative humidity, as the moisture-induced rancidity was evidently not extensive.

In the present work, carotenoids were isolated (1.2%) from crude palm oil and encapsulated with isabgol fiber (Psyllium husk). The efficiency of encapsulation was 82.23±1.42%. The morphology of the capsules showed rough surface texture with minimal pores. The amorphous natures of the nano-capsules was obvious from X-ray diffraction patterns. DSC studies showed high thermal stability of the nano-capsules between 20–120 °C. In vitro release studies revealed that controlled release from the nano-capsules could be achieved using isabgol fiber as encapsulant. However it was observed that the nano-capsules followed a non-Fickian diffusion pattern. Good DPPH-radical scavenging and metal-chelation activities were observed for encapsulated carotenoids. Shelf-life studies showed that the nano-capsules gradually degraded at 97% relative humidity, as the moisture-induced rancidity was evidently not extensive. [ABSTRACT FROM AUTHOR]

Background: Ferula assa-foetida is one of the common medicines that was used as antiseptic with a view to traditional uses, it can be used as a safe and effective drug to treat diseases particularly resistant bacterial infections. This study aims to product gelatin nano- capsules containing Ferula assa-foetida essential oil and investigate their antioxidant and antibacterial activities. Materials and Methods: This experimental study was performed on gelatin nano-capsules containing Ferula assa-foetida essential oil (FAO) (2, 4, 6 and 8% w/w), glycerol (25% w/w) as plasticizer and glutaraldehyde as cross-linker. The morphology, antioxidant and antibacterial activities and operation of the nano-capsules were assessed according to American Standards by Scanning Electron Microscopy, ABTS, and microbiological tests. Results: Gelatin nano-capsules exhibited low antioxidant and antibacterial activities while gelatin nano-capsules incorporated with FAO exhibited excellent antioxidant and antibacterial. The highest rates of these effects were seen merged with 8% of FAO. Conclusion: Gelatin nano-capsules merged with FAO have excellent physical form, as well as they are an appropriate antioxidant and antibacterial that have been considered to produce antoxidant and antibacterial drugs. [ABSTRACT FROM AUTHOR]

The investigation of the interaction in a tungsten–soot system containing excess soot under intensive mechanical treatment and annealing was made. The tungsten:soot molar ratio was varied from 1:1.3 to 1:2. Soot was taken in excess with respect to W in order to ensure obtaining WC without admixtures of W or W2C. An increase in mechanical treatment time from 10 to 30 min leads to the appearance of reflections corresponding to tungsten carbides. The final product of chemical reactions in preliminary activated and annealed at temperatures exceeding 923 K tungsten–soot mixtures with an excess of soot is WC, which is formed as nano-capsules with a nucleus size of 20–140 nm and a graphite shell 4–30 nm thick. Transmission electron microscope photographs of WC nanoencapsulated particles are presented. [Copyright &y& Elsevier]

The layer-by-layer approach is a highly versatile method for the fabrication of multilayered polymeric films and capsules. It has been widely investigated in research for various polyelectrolyte pairs and core template particles. However, the fabrication of nano-sized capsules at the larger scale is difficult and time consuming, due to the necessity of washing and centrifugation steps before the deposition of each polyelectrolyte layer. This results not only in a very long fabrication time, but also in the partial loss of particles during those intermediate steps. In this study, we introduced a continuous approach for the fabrication of multilayer polyelectrolyte based nano-capsules using calcium phosphate core nanoparticles and a tubular flow type reactor with the potential for synthesizing tens of milligrams of capsules per hour. Adsorption of the polyelectrolyte layer occurred in the tubing where particles and polyelectrolyte solution of choice were mixed, creating a layer of polyelectrolyte on the particles. After this, these newly surfaced-modified particles passed into the next segment of tubing, where they were mixed with a second polyelectrolyte of opposite charge. This process can be continuously repeated until the desired number of layers is achieved. One potential problem with this method concerned the presence of any excess polyelectrolyte in the tubing, so careful control of the amount of polymer added was crucial. It was found that slightly under dosing the amount of added polyelectrolyte ensured that negligible unadsorbed polyelectrolyte remained in solution. The particles created at each deposition step were stable, as they all had a zeta potential of greater than ±25mV. Furthermore the zeta potential measurements showed that charge reversal occurred at each stage. Having achieved the necessary number of polyelectrolyte layers, the calcium phosphate cores were easily removed via dissolution in either hydrochloric or acetic acid., (Copyright © 2016 Elsevier Inc. All rights reserved.)