Open Journal of Applied Sciences

Journal Information
ISSN / EISSN : 2165-3917 / 2165-3925
Published by: Scientific Research Publishing, Inc. (10.4236)
Total articles ≅ 881
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Wattevidanage J. Perera, Prasad Senadeera, Parthirage P. D. C. Perera, Derrick R. Kulatunge
Open Journal of Applied Sciences, Volume 12, pp 51-58; https://doi.org/10.4236/ojapps.2022.121005

Abstract:
Turmeric (Curcuma longa L.) is one of the essential condiments all over the world. Turmeric is an important medicine in the eastern medical systems and its therapeutic properties have been well recorded. Curcumin, commonly called diferuloyl methane (hydrophobic polyphenol), was studied extensively for its biological properties. Sri Lankan turmeric records relatively higher percentage (up to 9%) of curcumin. The bioactive compounds with insecticidal or pesticidal activity were studied from the Sri Lankan turmeric as there is an increasing demand for natural products to control ticks and fleas in dogs against the chemicals that induce some secondary effects. Fifty grams (50 g) of dried coarsely ground turmeric (Curcuma longa L.) was subjected to sequential extractions with four different solvents in ascending order of polarity using Soxhlet apparatus. The treatments consisted of solvent-fractionated turmeric extracts from hexane, dichloromethane (CH2Cl2), ethyl acetate (EtOAc) and Methanol (CH3OH) dissolved in the water to 100 ppm. The test carried out using a modified olfactometer and the degree of repellency of common tick species Rhipicephalus sanguineus was recorded. The hexane extract from dried turmeric powder showed the highest repellence of 80% whereas other fractions showed lesser repellence. Further studies in the direction of purification, dose dependent repellency and persistency.
Aristide H. W. Nakavoua, Anicet F. Binaki, Emmanuelle S. Ouenadio, Raymond G. Elenga, Vincent Verney
Open Journal of Applied Sciences, Volume 12, pp 42-50; https://doi.org/10.4236/ojapps.2022.121004

Abstract:
The work carried out here opens another perspective in the valorization of sweet potatoes produced in Congo Brazzaville other than those proposed by BOULA and all. We have shown in this work that the hydrophilic property of starch which limits the production of starch-based bioplastics can be inhibited by using the effects of photonic incandescence. Indeed, light significantly impacts the bioplastic matrix causing a decrease of the sites likely to bind water molecules. However, it would be desirable to apply rheology for a better follow-up of this cross-linking phenomenon. The synthesized retrograde bioplastic having undergone a photonic stress shows better physical properties to be used as packaging and thus to answer the environmental protection.
Ke Li, Jie Chen, Xiaoan Nie, Jianchun Jiang
Open Journal of Applied Sciences, Volume 12, pp 1-9; https://doi.org/10.4236/ojapps.2022.121001

Abstract:
In this paper, non-catalytic high temperature deacidification process of glycerol rich in acid oil was studied. Through orthogonal experiment, the primary and secondary order of influencing factors was temperature, glycerol dosage and reaction time, and the optimal process conditions were further verified: The ratio of fatty acid to glycerol is 1:1.2, the reaction temperature is 240°C, and the acid value can be reduced to 1.66 mg KOH/g for 2 h. In addition, the activation energy of the reaction was 54.93 kJ/mol by kinetic study. Combined with the K1 value of each reaction, it was confirmed that the temperature rise was conducive to the progress of the reaction. Finally, the high temperature ionization theory of glycerol is put forward, and the mechanism of auto-catalyzed deacidification reaction of glycerol is deduced by using this theory. This theory not only explains this study, but also perfectly explains the slow reaction time of low glycerol dosage.
Mohammad Farhadur Rahman, Nargish Jahan Ara, Sakib Hasan, Zubair Hasan
Open Journal of Applied Sciences, Volume 12, pp 892-900; https://doi.org/10.4236/ojapps.2022.126061

Abstract:
Waste water expulsion containing toxic and hazardous ingredients from textile industry is one of the biggest concerns in this modern age. N-doped nano composites as an efficient catalyst are playing a significant role in reducing the toxicity of that textile effluent. N-doped Ti-Mel capped Ag2S NCs (N-Ti-C/Ag2S NCs) and N-doped TiO2 capped Ag2S NCs (TiO2/Ag2S NCs) were synthesized via calcinations at 700°C, whereas Ag2S NCs was prepared by simple hydrothermal treatment process at 120°C and confirmed by FTIR and SEM (EDX). N-Ti-C/Ag2S NCs were applied in presence of reducing agent NaBH4 with a green method to decolorize the textile dyes Levafix Amber RR (LA) and Remazol Blue RR (RB). Moreover, Ag2S NCs, TiO2/Ag2S NCs, NaBH4 and TiO2 were also investigated. Using UV-visible spectroscopy the progress time was measured to decolorize textile dye RB and completed within 3.15 mins, 12.15 mins, 12.15 mins for N-Ti-C/Ag2S NCs, Ag2S NCs and TiO2/Ag2S NCs respectively, while for LA the catalytic reduction taken for the same NCs was 8.15 mins, 12.15 mins and 30.15 mins respectively. N-Ti-C/Ag2S NCs based catalyst afforded excellent catalytic reduction activity in both cases. Interestingly the effect of NaBH4 itself and TiO2 in presence of NaBH4 was less than 5% after 30 mins. Finally, the reusability for Ti-Mel capped Ag2S NCs evaluated up to four cycles.
Somaïla Koala, Yacouba Sawadogo, Jean Louis Zerbo
Open Journal of Applied Sciences, Volume 12, pp 1527-1546; https://doi.org/10.4236/ojapps.2022.129104

Abstract:
In this paper, we analyzed diurnal and annual seasonal variations of solar wind parameters such as interplanetary magnetic field (IMF), proton density (N), solar wind speed (V) and solar wind dynamic pressure (Pdym), during the solar cycles 23 and 24. Our study shows that strong geomagnetic disturbances are observed at the equinoxes during both solar cycles. The highest proton densities are observed at solstices during both solar cycles. The greatest solar wind speeds are observed at the equinoxes of solar cycle 23 and at the solstices of solar cycle 24. The highest solar wind dynamic pressures are observed at the solstices of both solar cycles. We also observed an asymmetrical evolution of the seasonal diurnal values of the solar wind parameters during the two cycles, except for the proton density. Our investigations also highlight the fact that the seasonal diurnal values of the solar wind parameters are significant at solar cycle 23 compared to solar cycle 24 characterized by a global weak in solar plasma conditions since the deep minimum that followed the solar cycle 23 leading to an absence of a persistent polar coronal hole. The drop observed in polar field and solar winds parameters during solar cycle 24 is reproduced on seasons (solstices and equinoxes). The solar cycle 23 and 24 appear to be two magnetically opposite solar cycles regardless the time scales.
Richard Tamba Simbo, Fayia Francis Nyuma, Maria Fe Rebecca D. Gueta
Open Journal of Applied Sciences, Volume 12, pp 1495-1504; https://doi.org/10.4236/ojapps.2022.129102

Abstract:
This study determined concentrations of iodine, consistent with WHO iodine fortification standards, in commercial edible salts mostly consumed in Harper. The following hypothesis was put forward in the research study; H1: the iodine content of the two brands of iodized salts is different from the WHO iodine fortification levels; H0: the iodine content of the two brands of iodized salts is not different from the WHO iodine fortification levels. The hypothesis was tested in MS Excel 2010 and 2016 via the T-Test function giving p-value = 0.1476 and p-value = 0.0395 indicative of no significant difference in the iodine concentration of the salts compared with the lower limit of WHO standard 20 mg·Kg-1 and huge contrast in the iodine concentration of the salts compared with the upper limit of WHO standard 40 mg·Kg-1 respectively. The UV spectrophotometric method was used to analyze and measure the iodine concentration in the twelve (12) samples of two different brands bought from grocery stores in Harper city. Results indicated that all samples of the two (2) brands of iodized salts contained iodine of no significant difference relative to the lower limit of WHO standard but far below the upper limit of the WHO standard. The study therefore recommends monitoring of commercial iodized salts by appropriate authorities in Harper to ascertain the WHO iodization fortification standards before reaching consumers.
Hsiao-Ming Chang, Chun-You Lin, Xiepin Zheng
Open Journal of Applied Sciences, Volume 12, pp 10-18; https://doi.org/10.4236/ojapps.2022.121002

Abstract:
This study aims to analyze the operational model of the local revitalization plan implemented in the indigenous tribes in Taiwan. It treated Namasia District of Kaohsiung City, Taiwan as the subject, and conducted an investigation by qualitative research. According to the findings, the practices of local revitalization are based on the following conditions: 1) local government leads the plan of revitalization; 2) it finds DNA to develop local revitalization; 3) it seeks investment from enterprises; 4) it accepts the assistance from academic and professional teams for the integration and development of innovative and creative products; 5) it reinforces the ethnic consciousness, supports local residents and industries, and participates in the execution of plans.
Peng Jiang, Yong Tian, Bo Wang, Nannan Zhang
Open Journal of Applied Sciences, Volume 12, pp 555-573; https://doi.org/10.4236/ojapps.2022.124039

Abstract:
As an important parameter of compressor impeller, the design value of blade outlet backsweep angle has a great influence on the performance of impeller. In this paper, six impellers with blade outlet backsweep angle β2B equal to 0°, 10°, 20°, 30°, 40°, and 50° were designed to evaluate the influences of impeller backsweep angle β2B on the performance, characteristics of gas flow and equivalent stress using computational fluid dynamics (CFD) and finite element analysis (FEA). Results indicated that the performance curve for the outlet backsweep blade angle β2B of 50° has the largest stable operating range. The isentropic efficiency of the impeller with backsweep angle β2B equal to 40° is 16.8% - 25.9% higher than that of the impeller with backsweep angle β2B equal to 0°. When the blade outlet backsweep angle is 30°, the equivalent stress distribution of the impeller is more uniform, the maximum equivalent stress is the smallest.
Mengxue Li
Open Journal of Applied Sciences, Volume 12, pp 421-433; https://doi.org/10.4236/ojapps.2022.124029

Abstract:
With the rapid increase of large-scale problems, the distribution of real-world datasets tends to be long-tailed. Existing solutions typically involve re-balancing strategies (i.e., re-sampling and re-weighting). Although they can significantly promote the classifier learning of deep networks, they will unexpectedly impair the representative ability of the learned deep features to a certain extent. Therefore, this paper proposes a dual-channel learning algorithm with involution neural networks (DC-Invo) to take care of representation learning and classifier learning concurrently. In this work, the most important thing is to combine ResNet and involution to obtain higher classification accuracy because of involution’s wider coverage in the spatial dimension. The paper conducted extensive experiments on several benchmark vision tasks including Cifar-LT, Imagenet-LT, and Places-LT, showing that DC-Invo is able to achieve significant performance gained on long-tailed datasets.
Fumio Maruyama
Open Journal of Applied Sciences, Volume 12, pp 541-554; https://doi.org/10.4236/ojapps.2022.124038

Abstract:
Extreme value theory provides methods to analyze the most extreme parts of data. We used the generalized extreme value (GEV) distribution to predict the ultimate 100 m, 200 m, 400 m, 4 × 100 m relay, and long jump records of male gold medalists at the Olympics. The diagnostic plots, which assessed the accuracy of the GEV model, were fitted to all event records, validating the model. The 100 m, 200 m, 400 m, 4 × 100 m, and long jump records had negative shape parameters and calculated upper limits of 9.58 s, 19.18 s, 42.97 s, 36.71 s, and 9.03 m, respectively. The calculated upper limit in the 100 m (9.58 s) was equal to the record of Usain Bolt (August 16, 2009). The 100 m and 200 m world records were close to the calculated upper limits, and achieving the calculated limit was difficult. The 400 m and 4 × 100 m relay world records were almost equal to the calculated upper limits and the 500-year return level estimate, and slight improvement was possible in both. At the Tokyo Olympics in August 2021, in the 100 m, 200 m, and 4 × 100 m, in one year the probability of occurrence for a record was about 1/30. In the 400 m and long jump, it was about 1/20. In the 100 m, 200 m, and 4 × 100 m relay, more difficult records show that a fierce battle has taken place.
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