Effect of a wavy interface on the natural convection of a nanofluid in a cavity with a partially layered porous medium using the ISPH method

The effect of a wavy nanofluid/porous-medium interface on the natural convection of a Cu–water nanofluid in a differentially heated non-Darcy porous cavity was investigated using the ISPH method. Wall boundary conditions were applied by improved scheme using the analytical kernel renormalization function and its gradient based on the quintic kernel function. The effect of the Rayleigh number and the Darcy number on the heat transfer of Cu–water nanofluid with a various solid volume fraction were studied. Results showed that higher amplitude, height, and the undulation number of the sinusoidal interface between the nanofluid and porous medium layer lead to a decrease in the average Nusselt number.     

Linearization of RF Power Amplifiers in Wideband Communication Systems by Adaptive Indirect Learning Using RPEM Algorithm

Mobile Networks and Applications - This paper proposes a new approach of digital predistortion (DPD) technique based on the adaptive indirect learning architecture (ILA) by using a recursive...     

Effects of Added Phosphates on Lipid Stability During Salt Curing and Rehydration of Cod (Gadus morhua)

Effects of added phosphates on retardation of lipid oxidation of salted cod during processing, storage and after rehydration were investigated. Lipid hydrolysis progress and development of color, primary and secondary lipid oxidation products and fluorescence intensities were determined. Added phosphates significantly retarded lipid hydrolysis and lipid oxidation progress, resulting in lower free fatty acid , lipid hydroperoxides (PV), thiobarbituric acid-reactive substances (TBARS) as well as fluorescence intensities (δF _or and δF _aq). Significant correlation between the lipid oxidation products (PV, TBARS, δF _or and δF _aq) and yellow/brownish discoloration (b* value) of salted cod was observed. Principal component analysis showed that TBARS, b* value and δF _or were the strongest indicators of lipid oxidation during salting and storage.     

Influence of some vegetable oils on the photocrosslinking of coatings based on an o-cresol novolac epoxy resin and a bis-cycloaliphatic diepoxide

The influence of cashew nut shell oil (CNO), epoxidized soybean oil (ESO), castor oil (CO), and dioctyl phtalate (DOP) on the photocrosslinking kinetics of UV curable mixtures containing an o-cresol novolac epoxy resin (CNE), a bis-cycloaliphatic diepoxide monomer (BCDE), and a triarylsulfonium salt (TAS) as a cationic photoinitiator has been studied. The formulation with a weight ratio CNE/BCDE/TAS of 60/40/5 was found to have the highest cure rate and the greatest final conversion of epoxy groups upon UV exposure. The presence of an unsaturated oil or of DOP in the UV curable formulation, at a content ranging from 0.07 to 0.79 mol/kg, was shown to increase the initial polymerization rate of the epoxy groups from 12 up to 31 mol/kg s, and the epoxy conversion after 18 s UV exposure from 80 up to 95%. It was found that the UV cured coatings containing CNO or DOP at concentrations between 0.3 and 0.6 mol/kg and ESO at concentrations between 0.12 and 0.19 mol/kg exhibit the best performance. These results were explained by a number of competitive factors, mainly the effects of the chemical structure and content of the oils and of DOP on the polarity, viscosity, compatibility, and internal filter effect of the UV curable resins, as well as by the characteristics of the tridimensional polymer networks formed upon UV exposure. The materials produced under the optimal conditions determined in this study can be used as high performance decorative and protective coatings and also as adhesives in different sectors of applications.     

Size and morphology-controlled synthesis of mesoporous hydroxyapatite nanocrystals by microwave-assisted hydrothermal method

We report the rapid microwave-assisted hydrothermal synthesis of mesoporous hydroxyapatite (HAp) nanocrystals with controlled size, morphology, and surface area using various organic modifiers as regulators. The products were analyzed for their crystalline nature, phase purity, morphology, particle size and pore size distribution. Results indicated that ascorbic acid, cetyltrimethyl ammonium bromide (CTAB) and polyvinylpyrrolidone (PVP) play an important role to obtain needle like, rod like and fiber like mesoporous HAp nanocrystals with different specific surface area by controlling growth habit of HAp along c-axis. In addition, the prepared samples were B-type carbonated HAp similar to bone minerals. Therefore, the present approach can be a promising way to obtain precursor for making tissue engineering scaffolds, drug/protein delivery carriers and bone fillers with tunable characteristics.     

Self-assembled poly(ethylene glycol) methyl ether-grafted gelatin nanogels for efficient delivery of curcumin in cancer treatment

Curcumin (CUR) is a natural active ingredient that attracted much attention for its chemotherapeutic activity against tumors without causing toxicity in healthy cells. However, it has certain limitations for being used in chemotherapy such as low aqueous solubility and hydrolytic instability in the physiological environment. In this study, self-assembled poly(ethylene glycol) methyl ether-grafted gelatin (Gel-mPEG) nanogels were fabricated as delivery systems to improve the applicability of CUR in cancer treatment. CUR-loaded Gel-mPEG nanogels exhibited desired size range, relatively colloidal stability, and provided enhanced CUR stability in aqueous solutions. Especially, they showed significant high CUR loading capacity and better anticancer activity than free CUR as compared to previously reported CUR-loaded nanogels according to the best of our knowledge. Moreover, the in vitro release of CUR from the nanogels was controlled and prolonged up to 96 h. These results demonstrated that Gel-mPEG nanogels are the promising modality for the efficient delivery of CUR in cancer treatment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47544.     

Vietnam's energy sector: A review of current energy policies and strategies

Since the introduction of market-oriented economy in 1986, Vietnam has made noticeable socio-economic progress. In this progress, the energy sector has played a vital role. This role is likely to deepen in the years to come as Vietnam strives to achieve even higher levels in economic progress. Such deepening in the role of energy, this paper argues, will heighten concerns about the security of energy supply, and economic, environmental, social and political consequences. In order to address these issues, Vietnam has over the last decade, developed a suite of energy policies. A deeper review of these policies suggests that they are typified by economic-growth orientation, exclusive focus on a single-sector or single issue, and largely neglect the significance of cross-sectoral and cross-thematic issues arising from the interdependencies between energy, economy, and the polity at large. The existing energy policy settings are, therefore, unlikely to be able to provide a satisfactory redress to the challenges noted above. This paper provides an overview of the current energy policies with a view to identify areas where further policy effort is needed in order to facilitate a sustainable development of the Vietnamese energy sector.     

Authenticity green coffee bean species and geographical origin using near-infrared spectroscopy combined with chemometrics

To prevent the adulteration of agricultural resources and provide a solution to enhance the green coffee bean supply chain, authentication using the near-infrared spectroscopy (NIRS) technique was investigated. Partial least square with discrimination analysis (PLS-DA) models combined with various preprocessing methods were built from NIR spectra of 153 Vietnamese green coffee samples. The model combined with the standard normal variate and the first order of derivative yielded excellent performance in predicting coffee species with the error cross-validation of 0.0261. PLS-DA model of mean centre and first-order derivative spectra also yielded good performance in verifying geographical indication of green coffee with the error of 0.0656. By contrast, the predicting abilities of post-harvest methods were poor. The overall results showed a high potential of the NIRS in online authentication practices.     

Solving distribution problems in content-based recommendation system with gaussian mixture model

Applied Intelligence - Recommendation systems play an important role in boosting purchasing consumption for many manufacturers by helping consumers find the most appropriate items. Furthermore,...