Laboratory investigations on the extraction of oil from vegetable oil-cakes with ethanol

1. Undue dilution of alcohol can be prevented by employing oleaginous materials of moisture content less than 1.0% for ethanol extraction.
2. The residual oil content of the meal depends on the particle size of the cake for a constant period of extraction.
3. Better quality oil in respect to color and F.F.A. is obtained with 95.6% ethanol extraction though the temperature of extraction is higher than the temperature employed with 98.6% ethanol.
4. F.F.A. of the extracted oils is low and within 1.0% for most of the oils, hence a reduction of refining loss. The color of safflower and peanut oils compares with the color of the screw-press oils.
5. In the case of cottonseed meats extraction, the cooking of meats results in a lighter color oil and increases the yield for the same period of extraction. Cottonseed extraction also illustrates the advantages of ethanol as the solvent for oil extraction.

     

Solubilities of vegetable oils in aqueous ethanol and ethanol-hexane mixtures

Summary The solubility of vegetable oils in aqueous ethanol depends on the concentration of alcohol and temperature of the system. At ordinary temperatures even absolute alcohol is not a good solvent for vegetable oils since the solubility is even less than 10 g. of oil per 100 g. of alcohol. Mowrah, safflower, peanut, and cottonseed oils are soluble in absolute alcohol at 70°C. All the oils investigated are found to be miscible above the boiling point of alcohol even if the concentration is 98%. In 95% ethanol they are miscible between 90° and 100°C. Addition of a good solvent, like n-hexane, increases the solubility of oils, and the solubility temperatures are lowered. From the results obtained by various methods of solubility determination it is found that the apparatus employed in the present work yields more reliable results by eliminating the visual observation of turbidity temperatures, ensuring vigorous stirring and allowing sufficient amount of time to attain equilibrium conditions in determining the solubilities of vegetable oils. Presented at fall meeting, American Oil Chemists' Society, Cincinnati, O., September, 30–October 2, 1957.     

Barrier,rheological, and antimicrobial properties of sustainable nanocomposites based on gellan gum/polyacrylamide/zinc oxide

In this study, we used a solution casting method to prepare gellan gum (G)-based ternary nanocomposite films containing polyacrylamide (P) and zinc oxide (ZnO) nanoparticles. All composites were prepared using the chemical cross-linker N,N-methylenebisacrylamide. The nanocomposites were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction, and scanning electron microscopy. Attenuated total reflectance FTIR revealed strong hydrogen bonding interactions among gellan gum, polyacrylamide, and ZnO, which enhanced the physiochemical, thermal, and mechanical properties of the GPZnO nanocomposites. The addition of ZnO nanoparticles increased the glass transition temperature (T_g: 181.8–196.3°C), thermal stability (T_5%: 87.8–96.5°C), and char yield (23.9–29.1%) of the GP composite films, as well as their the tensile strength (from 33.5 to 43.8 MPa) and ultraviolet (UV) blocking properties (~99.2% protection against UVB [280–320 nm]). ZnO significantly influenced the rheological properties of the GP composite. The prepared GP and GPZnO nanocomposites exhibited shear thinning behavior and their viscosities decreased when there is an increase in shear rate. Storage and loss modulus increased with frequency with the addition of ZnO nanoparticles. The GPZnO films exhibited reduced hydrophilicity, moisture content, and water barrier properties compared with the GP film. The GPZnO nanocomposites exhibited effective antimicrobial activity against six different pathogens. The prepared GPZnO films could be useful in biodegradable packaging applications.     

Development of nanocomposites for bone grafting

This article reviews nanocomposites focusing on their impact and recent trends in the field of bone grafting. Although autogenous- and allogeneic-bone grafts have been used for a long time in bone therapies, there is still a donor shortage and infection risk. As an alternative, synthetic biomaterials have been developed and clinically used as bone grafts, but most of them differ substantially from natural bone either compositionally or structurally. It remains a great challenge to design an ideal bone graft that emulates nature’s own structure. Owing to the composition and structural similarity to natural bone, most of the current investigations involve the use of nanocomposites, particularly hydroxyapatite/collagen system, as promising bone grafts, but it is surprising that none of the reports review the rationale and design strategy of such nanocomposites in detail for the benefit of researchers. Accordingly, this article addresses the state-of-the-art of those nanocomposites and provides suggestions for future research and development. This review provides an overview of the nanocomposite strategy of bone, bone grafting, synthetic approaches to bone structure, development of nanocomposites from the conventional monolithic biomaterials, and recently developed processing conditions for making nanocomposites. The review is expected to be useful for readers to gain an in-sight on the state-of-the-art of nanocomposites as a new class of synthetic bone grafts.     

Synthesis of silver-integrated silica nanostructures using rice hulls and their electrochemical performance for supercapacitor application

We report the synthesis of silver-integrated silica nanostructures using rice hulls and silver chloride through a facile thermal combustion process. The formation of mesoporous silica nanomatrix embedded with silver nanoparticles (SiO₂:Ag 5 wt% and SiO₂:Ag 10 wt%) was confirmed by XRD, FTIR, EDX, BET, and TEM analysis. Also, the obtained results from the above studies revealed that the concentration of silver ions significantly increases the particle size and number of silver nanoparticles formed in the silica matrix. The electrochemical performance was studied using silver-integrated silica nanostructures as a working electrode in KOH electrolyte. The maximum specific capacitance of SiO₂:Ag 5 wt%- and SiO₂:Ag 10 wt%-coated electrode was found to be 517 and 580 F/g at current density of 1 A/g. It was also found that SiO₂:Ag 10 wt% electrode exhibit an excellent stability with the capacitance retention of 94% than SiO₂:Ag 5 wt% (capacitance retention of 85%) after 1000 cycles at a current density of 1 A/g. These results may be attributed to the inherent characteristic of more silver nanoparticles present in the silica nanomatrix in SiO₂:Ag 10 wt%. The intrinsic characteristic of rice hull-derived silica nanostructures such as high surface area and mesoporous structure along with the advantage of silver nanoparticles (conductivity) can facilitate the Faradic redox processes at electrode surface which are responsible for the supercapacitive behavior of the prepared silver-integrated silica nanostructures.

     

Effect of brazing temperature on the microstructure of martensitic–austenitic steel joints

Dissimilar joining of reduced activation ferritic–martensitic steel to AISI 316LN austenitic stainless steel is carried out by brazing in inert atmosphere at three different temperatures, i.e. 980, 1020 and 1040°C using AWS BNi-2 powder. The braze joints are characterised by scanning electron microscopy, X-ray diffraction, micro-hardness measurement. With increasing brazing temperature from 980 to 1040°C, the approximate width of the braze layer decreases from 350 to 80?µm and hardness reduces from 600 to 410?VHN. However, not much difference is found in microstructure and hardness between braze joints produced at 1020 and 1040°C. With increasing brazing temperature, morphology and volume fraction of intermetallics formed in the braze layer change, thereby reducing the hardness variation between the braze layer and the base metal.     

The effect of UV light on the inactivation of Giardia lamblia and Giardia muris cysts as determined by animal infectivity assay (P-2951-01)

This study measured the effect of germicidal ultraviolet (UV) light on Giardia lamblia and Giardia muris cysts, as determined by their infectivity in Mongolian gerbils and CD-1 mice, respectively. Reduction of cyst infectivity due to UV exposure was quantified by applying most probable number techniques. Controlled bench-scale, collimated-beam tests exposed cysts suspended in filtered natural water to light from a low-pressure UV lamp. Both G. lamblia and G. muris cysts showed similar sensitivity to UV light. At 3 mJ/cm2, a dose 10-fold lower than what large-scale UV reactors may be designed to provide, > 2-log10 (99 percent) inactivation was observed. These results, combined with previously published data showing other protozoa and bacteria have similar, high sensitivity to UV light, establish that UV disinfection of drinking water is controlled by viruses which may require over 10-fold more UV dose for the same level of control.     

Milling and separation of the multi-component printed circuit board materials and the analysis of elutriation based on a single particle model

Electronic waste, in the form of printed circuit boards (PCBs) or printed wiring boards (PWBs), represents a significant and growing fraction of the waste generated in many communities. It is necessary to identify schemes to manage and dispose this waste in an environmentally safe manner. The present work, examines the use of mechanical means to separate the metallic and non-metallic components present in PCBs. The unique characteristics of PCB construction pose challenges to the mechanical means of separation. In view of these unique characteristics of PCBs, an empirical approach is suggested to evaluate the effectiveness of the mechanical separation process. Two milling operations were used to obtain the feed for the separation using elutriation. Compositions of different size fractions from the milling operations are presented. Experimental data from the separation process is presented and the extent of use of mechanical means that results in optimum separation is identified. The separation efficiency is analyzed in terms of composition, particle size and operating condition of the elutriation flow rate. A probabilistic analysis based on single particle settling velocity shows that separation results with uniform particle size fraction can be described effectively. However, the probabilistic analysis captures only the qualitative features with mixed particle sizes and components.     

Development of CeO2 nanorods reinforced electrodeposited nickel nanocomposite coating and its tribological and corrosion resistance properties

A simple electrodeposition technique was used to prepare Ni-CeO_2 nanorods composite coating(Ni-CeO_2 NRs) using Watt's nickel plating bath containing CeO_2 nanorods(NRs) as the reinforcement phase under optimized process conditions. The X-ray diffraction analysis(XRD) was used for the structural analysis of Ni-CeO_2 NRs composite coatings and their average crystalline size is ～22 nm for pure Ni and ～18 nm,respectively. The crystalline structure is fcc for the Ni-CeO_2 nanocomposite coatings. The surface morphology of the electrodeposited Ni-CeO_2 NRs composite coatings was analyzed by scanning electron microscopy(SEM). Microhardness of pure Ni and Ni-CeO_2 NRs composite coatings are found to be 253 HV and 824 HV, respectively. The inclusion of CeO_2 NRs increases the microhardness of Ni-CeO_2 NRs composite coatings. The corrosion resistance behavior of Ni-CeO_2 NRs composite coating was evaluated by Tafel polarization and AC impedance methods. It is revealed that CeO_2 NRs reinforced Ni matrix shows higher microhardness and corrosion resistance than existing reported electrodeposited pure Ni and CeO_2 nanoparticles reinforced Ni coatings.     

Effect of Laccase and Xylanase Enzyme Treatment on Chemical and Mechanical Properties of Banana Fiber

This work analyses the effect of Laccase and Xylanase enzyme treatment on chemical and mechanical properties of banana fiber. Properties such as chemical composition, density, tensile strength, and color were analyzed. The removal of lignin increased with increase in enzymes concentration. Lignin removal was observed to be higher for Laccase treatment. The hemicellulose removal was higher for Xylanase treatment and the results were confirmed by FTIR spectrum. It is evident that cellulose%, density and tensile strength increased up to 15% enzyme treatment concentration and then started declining at 20% enzyme concentration in the case of both enzymes, whereas the moisture regain percentage of the fiber decreased with increase in enzyme concentration. The effects of enzymatic treatments are clearly visible in the SEM images.