96 results on '"Arnold C. Alguno"'
Search Results
2. Investigating structural and optoelectronic properties of Cr-substituted ZnSe semiconductors
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Muhammad Aamir Iqbal, Sunila Bakhsh, Siti Sarah Maidin, Kareem Morsy, Jeong Ryeol Choi, and Arnold C. Alguno
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Cr-substituted ZnSe semiconductors ,Cubic symmetry ,Concentration dependency ,Bandgap ,Density of states ,Infrared absorbance ,Medicine ,Science - Abstract
Abstract The optoelectronic and structural characteristics of the Zn1−xCrxSe (0 ≤ x ≤ 1) semiconductor are reported by employing density functional theory (DFT) within the mBJ potential. The findings revealed that the lattice constant decreases with increasing Cr concentration, although the bulk modulus exhibits the opposite trend. ZnSe is a direct bandgap material; however, a change from direct to indirect electronic bandgap has been seen with Cr presence. This transition is caused by structural alterations by Cr and defects forming, which results in novel optical features, including electronic transitions. The electronic bandgap decreases from 2.769 to 0.216 eV, allowing phonons to participate and improving optical absorption. A higher concentration of Cr boosts infrared absorption and these Cr-based ZnSe (ZnCrSe) semiconductors also cover a wider spectrum in the visible range from red to blue light. Important optical parameters such as reflectance, optical conductivity, optical bandgap, extinction coefficient, refractive index, magnetization factor, and energy loss function are discussed, providing a theoretical understanding of the diverse applications of ZnCrSe semiconductors in photonic and optoelectronic devices.
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- 2024
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3. Influence of the Gold Nanoparticle Size on the Colorimetric Detection of Histamine
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Rolen Brian P. Rivera, Romnick B. Unabia, Renzo Luis D. Reazo, Melbagrace A. Lapening, Ryan M. Lumod, Archie G. Ruda, Jahor L. Omping, Miceh Rose D. Magdadaro, Noel Lito B. Sayson, Felmer S. Latayada, Rey Y. Capangpangan, Gerard G. Dumancas, Roberto M. Malaluan, Arnold A. Lubguban, Gaudencio C. Petalcorin, and Arnold C. Alguno
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Chemistry ,QD1-999 - Published
- 2024
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4. A novel naturally superoleophilic coconut oil-based foam with inherent hydrophobic properties for oil and grease sorption
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Tomas Ralph B. Tomon, Christine Joy M. Omisol, Blessy Joy M. Aguinid, Karyl Xyrra L. Sabulbero, Arnold C. Alguno, Roberto M. Malaluan, and Arnold A. Lubguban
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Medicine ,Science - Abstract
Abstract Absorption methods using polyurethane foams (PUFs) have recently gained popularity in treating oil spills. However, conventional petroleum-based PUFs lack selectivity and are commonly surface-modified using complicated processes that require toxic and harmful solvents to enhance their hydrophobicity and oil sorption capacities. In this paper, a novel naturally superoleophilic foam with inherent hydrophobic properties has been developed through the conventional one-shot foaming method with the integration of coconut oil-based polyol. This bio-based polyol was explicitly handpicked as it is chiefly saturated, highly abundant, and inexpensive. The foam is characterized by an oil sorption capacity range of 14.89–24.65 g g−1 for different types of oil, equivalent to 578–871 times its weight. Its hydrophobic behavior is expressed through a water contact angle of ~ 139°. The foam also showcased excellent chemical stability and high recyclability without a significant loss in absorption capacity after 20 cycles. The incorporation of the coconut oil-based polyol is also shown to improve the morphological, mechanical, and thermal behavior of the foam. It can be inferred from these findings that this novel material holds great potential for revolutionizing sorbents, pioneering a more sustainable and eco-friendly functional material produced via a facile method.
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- 2024
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5. Dopamine-Functionalized Gold Nanoparticles for Colorimetric Detection of Histamine
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Romnick B. Unabia, Renzo Luis D. Reazo, Rolen Brian P. Rivera, Melbagrace A. Lapening, Jahor L. Omping, Ryan M. Lumod, Archie G. Ruda, Noel Lito B. Sayson, Gerard Dumancas, Roberto M. Malaluan, Arnold A. Lubguban, Gaudencio C. Petalcorin, Rey Y. Capangpangan, Felmer S. Latayada, and Arnold C. Alguno
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Chemistry ,QD1-999 - Published
- 2024
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6. Facile Synthesis of Band Gap-Tunable Kappa-Carrageenan-Mediated C,S-Doped TiO2 Nanoparticles for Enhanced Dye Degradation
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Daisy Jane D. Erjeno, Dan Michael A. Asequia, Carlo Kurt F. Osorio, Christine Joy M. Omisol, Andrei E. Etom, Renzo Miguel R. Hisona, Amierson C. Tilendo, Ann Pearl G. Triana, Gerard G. Dumancas, Joshua B. Zoleta, Arnold C. Alguno, Roberto M. Malaluan, and Arnold A. Lubguban
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Chemistry ,QD1-999 - Published
- 2024
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7. Development of High-Performance Coconut Oil-Based Rigid Polyurethane-Urea Foam: A Novel Sequential Amidation and Prepolymerization Process
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Louell Nikki A. Hipulan, Roger G. Dingcong, Dave Joseph E. Estrada, Gerard G. Dumancas, John Christian S. Bondaug, Arnold C. Alguno, Hernando P. Bacosa, Roberto M. Malaluan, and Arnold A. Lubguban
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Chemistry ,QD1-999 - Published
- 2024
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8. Flexible Polyurethane Foams Modified with Novel Coconut Monoglycerides-Based Polyester Polyols
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Christine Joy M. Omisol, Blessy Joy M. Aguinid, Gerson Y. Abilay, Dan Michael Asequia, Tomas Ralph Tomon, Karyl Xyrra Sabulbero, Daisy Jane Erjeno, Carlo Kurt Osorio, Shashwa Usop, Roberto Malaluan, Gerard Dumancas, Eleazer P. Resurreccion, Alona Lubguban, Glenn Apostol, Henry Siy, Arnold C. Alguno, and Arnold Lubguban
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Chemistry ,QD1-999 - Published
- 2024
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9. Rotor angle stability and voltage stability improvement of highly renewable energy penetrated western grid of Bangladesh power system using FACTS device
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Pollen Barua, Vineet Shekher, Vivek Kumar, Md Fahim Ansari, Arnold C. Alguno, and Ratul Barua
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Renewable energy system ,wind turbine generator ,solar photovoltaic generator ,power oscillation damper ,stability ,TCSC ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
AbstractMost of the generations in Bangladesh power system are based on fossil fuels which is 99% of its total generation. Following other countries, Bangladesh is also planning to adopt renewable energy system (RES). It has a plan to incorporate 55 MW wind turbine generator (WT) and 100 MW solar photovoltaic generator (PV) in Western grid of its power system. Though RES is green energy but from stability aspect it needs to be studied as RES has limitations in generating reactive power and maintaining inertia. So, voltage stability and rotor angle stability should be given more attention. However, if any stability problem arises, flexible alternating current transmission system (FACTS) devices can be adopted. With a tuned power oscillation damper, FACTS can reduce the expected rotor angle and voltage stability problem which are associated with RES. This paper examines the stability of the Western grid with the incorporation of hybrid energy of both wind and solar power and shows the positive effect of FACTS devices like thyristor controlled series compensator and static synchronous compensator with respective tuned controller. In present paper, the combination of WT and PV is also examined which shows only incorporation of WT reduces both the steady and dynamic stability more than the only adoption of PV. Inclusion of both WT and PV, reduce the both types of stability more than their individual inclusion. This paper shows that FACTS can improve the stability with individual or both kinds of RES penetration.
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- 2023
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10. Improving the efficiency of dye-sensitized solar cells based on rare-earth metal modified bismuth ferrites
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Maham Khan, Muhammad Aamir Iqbal, Maria Malik, Syed Usama Mauood Hashmi, Sunila Bakhsh, Muhammad Sohail, Muhammad Tariq Qamar, Mohammed Al-Bahrani, Rey Y. Capangpangan, Arnold C. Alguno, and Jeong Ryeol Choi
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Medicine ,Science - Abstract
Abstract This study reports light energy harvesting characteristics of bismuth ferrite (BiFeO3) and BiFO3 doped with rare-earth metals such as neodymium (Nd), praseodymium (Pr), and gadolinium (Gd) dye solutions that were prepared by using the co-precipitation method. The structural, morphological, and optical properties of synthesized materials were studied, confirming that 5–50 nm sized synthesized particles have a well-developed and non-uniform grain size due to their amorphous nature. Moreover, the peaks of photoelectron emission for bare and doped BiFeO3 were observed in the visible region at around 490 nm, while the emission intensity of bare BiFeO3 was noticed to be lower than that of doped materials. Photoanodes were prepared with the paste of the synthesized sample and then assembled to make a solar cell. The natural and synthetic dye solutions of Mentha, Actinidia deliciosa, and green malachite, respectively, were prepared in which the photoanodes were immersed to analyze the photoconversion efficiency of the assembled dye-synthesized solar cells. The power conversion efficiency of fabricated DSSCs, which was confirmed from the I–V curve, is in the range from 0.84 to 2.15%. This study confirms that mint (Mentha) dye and Nd-doped BiFeO3 materials were found to be the most efficient sensitizer and photoanode materials among all the sensitizers and photoanodes tested.
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- 2023
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11. Basic concepts, advances and emerging applications of nanophotonics
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Muhammad Aamir Iqbal, Maria Malik, Nadia Anwar, Sunila Bakhsh, Saher Javeed, Siti Sarah Maidin, Kareem Morsy, Rey Y. Capangpangan, Arnold C. Alguno, and Jeong Ryeol Choi
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Basic concepts ,Confinements ,Nonlinear optics ,Plasmonics ,Photovoltaics ,Biomedical applications ,Chemistry ,QD1-999 - Abstract
Nanophotonics includes a diverse set of nontrivial physical processes, such as radiation-matter interaction, near-field optical microscopy, and the fabrication of nanophotonic materials, which extend far beyond diffraction limits. These effects have created new opportunities for a number of applications in nonlinear optics, light harvesting, media transmission, optical and biosensing, luminescence, and display technology. Emerging technologies in numerous optical systems, involving photon interaction with nanostructured materials at extremely small scales play a crucial role in improving our daily lives. The goal along this line is to develop nanometer-sized devices and equipment for efficient control and influence of photonic processes, in addition to slowing down the speed of photons. The industrial revolution has greatly impacted this multidisciplinary discipline, allowing researchers to discover new avenues in design, applied science, chemistry, physical science, and biological technology. This review familiarizes readers with the basic concepts of photonic nanostructures, including photonic nanoscale interactions, nanoconfinement, characteristics of nonlinear optical phenomena, and the use of photonic nanostructures in innovative domains such as light harvesting, theragnostic, metasurfaces, photovoltaics and plasmonics applications.
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- 2023
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12. Producing polyglycerol polyester polyol for thermoplastic polyurethane application: A novel valorization of glycerol, a by-product of biodiesel production
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Mike Jhun P. Calderon, Gerard G. Dumancas, Carlo S. Gutierrez, Alona A. Lubguban, Arnold C. Alguno, Roberto M. Malaluan, and Arnold A. Lubguban
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Thermoplastic polyurethane ,Glycerol ,Polyglycerol ,Bio-based ,Coconut oil-based polyol ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The production of biodiesel generates glycerol as a by-product that needs valorization. Glycerol, when converted to polyglycerol, is a potential polyol for bio-based thermoplastic polyurethane (TPU) production. In this study, a novel polyglycerol polyester polyol (PPP) was developed from refined glycerol and coconut oil-based polyester polyol. Glycerol was first converted to glycerol acetate and then polymerized with coconut oil-based polyester polyol (CPP) as secondary polyol and phthalic anhydride. The resulting PPP polymerized at 220 °C and OH:COOH molar ratio of 2.5 exhibited an OH number of
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- 2023
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13. Ab-initio study of pressure influenced elastic, mechanical and optoelectronic properties of Cd0.25Zn0.75Se alloy for space photovoltaics
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Muhammad Aamir Iqbal, Maria Malik, Wajeehah Shahid, Shaheen Irfan, Arnold C. Alguno, Kareem Morsy, Rey Y. Capangpangan, Phuong V. Pham, and Jeong Ryeol Choi
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Medicine ,Science - Abstract
Abstract The optoelectronic properties of the ternary Cd0.25Zn0.75Se alloy are reported under the influence of a high pressure ranging from 0 to 25 GPa, within a modified Becke–Jhonson potential using density functional theory. This alloy has a cubic symmetry, is mechanically stable, and its bulk modulus rises with pressure. It is observed to be a direct bandgap material with a bandgap energy that increases from 2.37 to 3.11 eV with rise in pressure. Pressure changes the optical and electronic properties, causing the absorption coefficient to rise and absorb visible green-to-violet light. The static dielectric constant, along with the static index of refraction, both increase under the influence of pressure. Optical constants, including dielectric constant, optical conductivity, refractive index, extinction coefficient, and reflection, are also investigated and discussed. This DFT forecast explores important research directions for the usage of the CdZnSe semiconductor alloys in the manufacturing of space photovoltaic and optoelectronic devices operating at different pressures.
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- 2022
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14. Optimizing the Parameters of Spark Plasma Sintering to Enhance the Hardness of MgO/TiC Composites
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Sai Ashish Kumar Karanam, R. Rathinam, Pradeep Kumar Mouria, Arnold C. Alguno, Rey Y. Capangpangan, Tariku Achamyeleh, Jose Luis Arias Gonzales, Vijay Kumar Sharma, and T. Stephen Livingston
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Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
In this research, the first work was carried out to manufacture MgO-based metal matrix composite containing 3 wt%. Sintering parameters, such as temperature, pressure, and time were subjected to Taguchi analysis to identify the most significant effect on magnesium oxide physical and mechanical characteristics. The impact of each sintering parameter explores using the analysis of variance-structure and microstructure analysis using XRD and EDS-equipped FE-SEM. The mechanical properties of the composite are evaluated by testing its Rockwell hardness (HR) and Vickers hardness (HV). The results showed that sintering temperature was the most influential of the sintering factors on microhardness. Densification at its peak was 100%, while it peaked at 62.19 Rockwell hardness and 58.7 Vickers hardness.
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- 2023
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15. Improvised centrifugal spinning for the production of polystyrene microfibers from waste expanded polystyrene foam and its potential application for oil adsorption
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Marco Laurence M. Budlayan, Jonathan N. Patricio, Jeanne Phyre Lagare-Oracion, Susan D. Arco, Arnold C. Alguno, Antonio Basilio, Felmer S. Latayada, and Rey Y. Capangpangan
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Expanded polystyrene foam ,Polystyrene microfiber ,Centrifugal spinning ,Oil adsorption ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Abstract A straightforward approach to recycle waste expanded polystyrene (EPS) foam to produce polystyrene (PS) microfibers using the improvised centrifugal spinning technique is demonstrated in this work. A typical benchtop centrifuge was improvised and used as a centrifugal spinning device. The obtained PS microfibers were characterized for their potential application for oil adsorption. Fourier transform infrared spectroscopy results revealed similarity on the transmission bands of EPS foam and PS microfibers suggesting the preservation of the EPS foam’s chemical composition after the centrifugal spinning process. Scanning electron microscopy displayed well-defined fibers with an average diameter of 3.14 ± 0.59 μm. At the same time, energy dispersive X-ray spectroscopy revealed the presence of carbon and oxygen as the primary components of the fibers. Contact angle (θCA) measurements showed the more enhanced hydrophobicity of the PS microfiber (θCA = 100.2 ± 1.3°) compared to the untreated EPS foam (θCA = 92.9 ± 3.5°). The PS microfiber also displayed better oleophilicity compared to EPS foam. Finally, the fabricated PS microfibers demonstrated promising potential for oil removal in water with a calculated sorption capacity value of about 15.5 g/g even at a very short contact time. The fabricated PS fiber from the waste EPS foam may provide valuable insights into the valorization of polymeric waste materials for environmental and other related applications.
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- 2021
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16. Extreme Gradient Boosting Algorithm for Predicting Shear Strengths of Rockfill Materials
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Mahmood Ahmad, Ramez A. Al-Mansob, Kazem Reza Kashyzadeh, Suraparb Keawsawasvong, Mohanad Muayad Sabri Sabri, Irfan Jamil, and Arnold C. Alguno
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Electronic computers. Computer science ,QA75.5-76.95 - Abstract
For the safe and economical construction of embankment dams, the mechanical behaviour of the rockfill materials used in the dam’s shell must be analyzed. The characterization of rockfill materials with specified shear strength is difficult and expensive due to the presence of particles greater than 500 mm in diameter. This work investigates the feasibility of using an extreme gradient boosting (XGBoost) computing paradigm to estimate the shear strength of rockfill materials. To train and validate the proposed XGBoost model, a total of 165 databases obtained from the literature are chosen. The XGBoost model was compared against support vector machine (SVM), adaptive boosting (AdaBoost), random forest (RF), and K-nearest neighbor (KNN) models described in the literature. XGBoost beats SVM, RF, AdaBoost, and KNN models in terms of performance evaluation metrics such as coefficient of determination (R2), Nash–Sutcliffe coefficient (NSE), and error in the root mean square ratio (RMSE) to the standard deviation of the measured data (RSR). The results demonstrated that the XGBoost model has the highest prediction performance with (R2 = 0.9707, NSE = 0.9701, and RSR = 0.1729), followed by the SVM model with (R2 = 0.9655, NSE = 0.9639, and RSR = 0.1899), RF (R2 = 0.9545, NSE = 0.9542, and RSR = 0.2140), the AdaBoost model with (R2 = 0.9390, NSE = 0.9388, and RSR = 0.2474) and the KNN model with (R2 = 0.6233, NSE = 0.6180, and RSR = 0.6181). A sensitivity analysis has been conducted to ascertain the impact of each investigated input parameter. This study demonstrates that the established XGBoost model for estimating the shear strength of rockfill materials is reliable.
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- 2022
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17. Optimizing the Mechanical and Microstructure Characteristics of Stir Casting and Hot-Pressed AA 7075/ZnO/ZrO2 Composites
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P. Satishkumar, C. Saravana Murthi, Rohinikumar Chebolu, Yenda Srinivasa Rao, Rey Y. Capangpangan, Arnold C. Alguno, Vishnu Prasad Yadav, M. Chitra, and Mahesh Gopal
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Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
The composite was made using the stir cast manufacturing method. Many parameters, like stirring speed, stirring time, ZrO2% reinforcement, and cast temperature, are evaluated in a Taguchi experimental design to see how they affected the composite properties. In terms of composite properties, ZrO2% reinforcement and the stir speed have the most significant impact. There were 25.02% gains in ultimate tensile strength and hardness, as well as a decrease in composite wear loss, when the optimal stir casting parameters were used compared to the initial stir casting settings. To get insight into the process and the qualities of the composite, the hot-pressing parameters were studied. Pressure, followed by temperature, is the most critical factor in determining the properties of composites. When a hot-pressing setting was determined to reduce the wear loss by a significant 39.3%, it was deemed perfect by the superranking concept. Under ideal conditions, hot-pressing procedures reduced wear loss by 40.8% while boosting ultimate tensile strength and hardness by 19.83% and 9.6%, respectively. The resulting microstructures and worn surface morphologies from stir casting and hot pressing show vastly different properties.
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- 2022
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18. Prediction of Rockburst Intensity Grade in Deep Underground Excavation Using Adaptive Boosting Classifier
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Mahmood Ahmad, Herda Yati Katman, Ramez A. Al-Mansob, Feezan Ahmad, Muhammad Safdar, and Arnold C. Alguno
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Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Rockburst phenomenon is the primary cause of many fatalities and accidents during deep underground projects constructions. As a result, its prediction at the early design stages plays a significant role in improving safety. The article describes a newly developed model to predict rockburst intensity grade using Adaptive Boosting (AdaBoost) classifier. A database including 165 rockburst case histories was collected from across the world to achieve a comprehensive representation, in which four key influencing factors such as maximum tangential stress of the excavation boundary, uniaxial compressive strength of rock, tensile rock strength, and elastic energy index were selected as the input variables, and the rockburst intensity grade was selected as the output. The output of the AdaBoost model is evaluated using statistical parameters including accuracy and Cohen's kappa index. The applications for the aforementioned approach for predicting the rockburst intensity grade are compared and discussed. Finally, two real-world applications are used to verify the proposed AdaBoost model. It is found that the prediction results are consistent with the actual conditions of the subsequent construction.
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- 2022
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19. Investigation of Mechanical Behavior and Microstructure Analysis of AA7075/SiC/B4C-Based Aluminium Hybrid Composites
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HassabAlla M. A. Mahmoud, P. Satishkumar, Yenda Srinivasa Rao, Rohinikumar Chebolu, Rey Y. Capangpangan, Arnold C. Alguno, Mahesh Gopal, A. Firos, and Murthi C. Saravana
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Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
The microstructure and mechanical properties of an MMC based on AA 7075 and strengthened through silicon carbide (SiC) as well as boron carbide (B4C) elements were studied. The (SiC + B4C) combination was used in various weight percentages of 4, 8, 12, and 16% to create the hybrid composites utilizing the traditional stir casting procedure. XRD and SEM measurements were used to investigate the dispersion of the reinforced particles. For example, microhardness, impact strength, and ultimate tensile strength were measured on hybrid composites at room temperature. The density and porosity of the materials were also studied. The researchers found that increasing the weight percentage of the (SiC + B4C) mixture resulted in a small drop in % elongation. However, hybrid composites comprising 16% (SiC + B4C) weight reduction showed some decrease in hardness and tensile strength. Equated to unreinforced alloys, the hardness and tensile strength of hybrid composites rise by 8% and 21%, respectively. Reinforcement also resulted in a decrease in impact strength and density, as well as an increase in porosity.
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- 2022
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20. Investigation of Mechanical and Tribological Properties of AA6061/MWCNT/B4C Hybrid Metal Matrix Composite
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P. Satishkumar, N. Natarajan, Rajasekaran Saminathan, J. Justin Maria Hillary, Biru Birhanu, Arnold C. Alguno, Rey Y. Capangpangan, Vishnu Raj, and Stephen Livingston
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Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Carbon nanotubes (CNTs) and graphene, in particular, have been the subject of many recent studies since their discovery in the early 2000s. Because of their unusual properties, carbon nanotubes (CNTs) have piqued the interest of scientists across a wide range of disciplines. An Al matrix was reinforced with powder metallurgy-fabricated B4C and CNT composites. The nanocomposite aluminium matrix was examined for tribological behaviour, density, stiffness, and compressive strength before and after hot isostatic pressing (HIP). Scanning electron microscopy and TEM were used to analyze the carbon nanotubes and their hybrid counterparts (SEM). The density of nanocomposites was reduced by 38% without HIP but by 45% after it was added to the mixture. Hardness was also increased by 40%, but following HIP, the hardness rose to 67%. Before and after HIP, the compression strength increased by 39% and 60%, respectively. HIP improves the wear rate by 45%, and B4C and CNTs improve the coefficient of friction by 20% in all volume fractions but only by 48% in the case of nanocomposites.
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- 2022
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21. Prediction of Liquefaction-Induced Lateral Displacements Using Gaussian Process Regression
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Mahmood Ahmad, Maaz Amjad, Ramez A. Al-Mansob, Paweł Kamiński, Piotr Olczak, Beenish Jehan Khan, and Arnold C. Alguno
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lateral displacement ,liquefaction ,Gaussian process regression ,sensitivity analysis ,machine learning ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
During severe earthquakes, liquefaction-induced lateral displacement causes significant damage to designed structures. As a result, geotechnical specialists must accurately estimate lateral displacement in liquefaction-prone areas in order to ensure long-term development. This research proposes a Gaussian Process Regression (GPR) model based on 247 post liquefaction in-situ free face ground conditions case studies for analyzing liquefaction-induced lateral displacement. The performance of the GPR model is assessed using statistical parameters, including the coefficient of determination, coefficient of correlation, Nash–Sutcliffe efficiency coefficient, root mean square error (RMSE), and ratio of the RMSE to the standard deviation of measured data. The developed GPR model predictive ability is compared to that of three other known models—evolutionary polynomial regression, artificial neural network, and multi-layer regression available in the literature. The results show that the GPR model can accurately learn complicated nonlinear relationships between lateral displacement and its influencing factors. A sensitivity analysis is also presented in this study to assess the effects of input parameters on lateral displacement.
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- 2022
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22. Biosynthesizing Cassia fistula Extract-Mediated Silver Nanoparticles for MCF-7 Cell Lines Anti-Cancer Assay
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Rija Abaid, Maria Malik, Muhammad Aamir Iqbal, Mariam Malik, Zubeda Shahwani, Taha Zaid Ali, Kareem Morsy, Rey Y. Capangpangan, Arnold C. Alguno, and Jeong Ryeol Choi
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General Chemical Engineering ,General Chemistry - Published
- 2023
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23. Synthesis and Characterization of Ferric Vanadate Nanorods for Efficient Electrochemical Detection of Ascorbic Acid
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Nadia Anwar, Muhammad Munir Sajid, Muhammad Aamir Iqbal, Haifa Zhai, Muqarrab Ahmed, Bushra Anwar, Kareem Morsy, Rey Y. Capangpangan, Arnold C. Alguno, and Jeong Ryeol Choi
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General Chemical Engineering ,General Chemistry - Published
- 2023
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24. Analyzing pH-dependent structural characteristics and optical transmittance of titanium dioxide
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Nadia Anwar, Muhammad Aamir Iqbal, Muqarrab Ahmed, Bushra Anwar, Iqra Abbas, Syeda Tehreem Iqbal, Fouzia Anwar, Nosheen Mushahid, Rey Y. Capangpangan, and Arnold C. Alguno
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General Physics and Astronomy ,Physical and Theoretical Chemistry ,Mathematical Physics - Abstract
The use of titanium dioxide (also known as titania) in solar cells, biomaterials, and photocatalytic processes has generated an ever-increasing amount of interest. Titania is widely used in a variety of applications because it is nanocrystalline, chemically stable, has a high refractive index, is mechanically hard, and transmits visible light well. In this work, titania nanoparticles were formed via sol–gel synthesis, wherein the effect of varying pH values such as 3, 5, 7, 9, and 11 has been investigated on the synthesized nanoparticles by studying their structural characteristics and analyzing their optical transmittance. Structural analysis of the synthesized TiO2 shows formation of the brookite phase at all pH values under as-synthesized conditions. Moreover, structural parameters including crystallite size, dislocation density, and unit cell volume were also calculated. Cell volume was calculated at various pH levels and measured between 255.7 and 257.2 Å3. Optical analysis shows a transmission increase with a pH increase, and maximum transmission has been observed above 80% for a pH value of 11.
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- 2023
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25. A novel reaction mechanism for the synthesis of coconut oil-derived biopolyol for rigid poly(urethane-urea) hybrid foam application
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Roger G. Dingcong, Roberto M. Malaluan, Arnold C. Alguno, Dave Joseph E. Estrada, Alona A. Lubguban, Eleazer P. Resurreccion, Gerard G. Dumancas, Harith H. Al-Moameri, and Arnold A. Lubguban
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General Chemical Engineering ,General Chemistry - Abstract
Synthesis of a coconut oil-based biopolyol via sequential glycerolysis and amidation; and its subsequent use as a sole polyol for rigid poly(urethane-urea) hybrid foam production.
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- 2023
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26. Controlling the Particle Size and Absorption Spectra of Honey Mediated Green Synthesis of Silver Nanoparticles for Antibacterial Application
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Aaron Andrew B. Mutia, Rey Marc T. Cumba, Rey Y. Capangpangan, and Arnold C. Alguno
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Microbiology (medical) ,Immunology ,Immunology and Allergy - Abstract
Silver nanoparticles were synthesized using locally purchased honey and silver nitrate solution. This method provides a simplistic and straightforward approach to the formation of silver nanoparticles. The silver nanoparticles with varying amounts of silver nitrate solution were characterized using ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy. In addition, dynamic light scattering characterization was used to determine the average size and size distribution of silver nanoparticles. Experimental results revealed that varying the amount of silver nitrate solution can control the size and absorption spectra of silver nanoparticles. A large amount of silver nitrate solution will exhibit a peak in the higher wavelength. The shifting of the absorption peaks at 401, 406, 407, 408, and 409 nm are believed to be related to the wavelength of the surface plasmon resonance. Moreover, a larger amount of silver nitrate solution also results in an increasing size with 27.2, 57.9, and 63.4 nm as revealed in the size distribution via dynamic light scattering. This green synthesis method of silver nanoparticles will provide a cost-effective production as an alternative to commercial antibacterial agents.
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- 2022
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27. Effects of Reaction Temperature on the Antibacterial Activity of Silver Nanoparticles Synthesized from Psidium guajava Leaf Extract
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Lloyd Allan T. Cabañog, Rey Marc T. Cumba, Melania Enot, Rey Y. Capangpangan, and Arnold C. Alguno
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Microbiology (medical) ,Immunology ,Immunology and Allergy - Abstract
Silver nanoparticles have been well known to possess efficient antibacterial properties. Many studies conducted on silver nanoparticles synthesized in different routes, from physical methods to chemical techniques to biological synthesis. In this study, the biological route was utilized using Psidium guajava leaves extract mixed with silver nitrate to synthesize silver nanoparticles. In addition, syntheses were done at varying temperatures to investigate its effect over antibacterial properties of the silver nanoparticles obtained. Results showed blueshifting of UV-Vis peaks suggesting decrease in particle size as synthesis temperature increases. FTIR also showed that the synthesized nanoparticles may have been capped by phenolic compounds from the biomolecules in guava leaves. Finally, antibacterial tests via Disc Diffusion Test suggested that the silver nanoparticles biologically synthesized at higher temperatures are more effective bactericides than those synthesized at lower temperatures as indicated by the measured zones of inhibition.
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- 2022
- Full Text
- View/download PDF
28. Future of Water/Wastewater Treatment and Management by Industry 4.0 Integrated Nanocomposite Manufacturing
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Jean Yves Uwamungu, Pawan Kumar, Ahmed Alkhayyat, Tasaddaq Younas, Rey Y. Capangpangan, Arnold C. Alguno, and Isaac Ofori
- Subjects
Article Subject ,General Materials Science - Abstract
Innovative technologies enable businesses to stay competitive in marketplace while also increasing profits in manufacturing of nanocomposites for water treatment. Aforementioned driving factors resulted in adoption of a number of innovative technologies, and no other trend has had a greater impact in recent years than Industry 4.0. Industry 4.0 is a comprehensive term that encompasses data management, manufacturing competitiveness, manufacturing processes, and efficiency. The term “Industry 4.0” refers to a group of key enabler technologies, such as cyber physical models, Internet of Things (IoT), artificial intelligence (AI), and big data analytics, including embedded devices which are all significant components to the mechanized and digitized industrial environments. AI approaches have been used for water treatment processes as well as desalination in recent years for optimizing the process along with providing realistic answers to water scarcity and water pollution-related issues. AI applications have been used to predict and minimize water treatment process operational costs by lowering costs and optimizing chemical utilization. Several AI models are successful and accurate in predicting effectiveness of various adsorbents used in the removal process of a variety of contaminants from water. To identify the current level of research and future development prospects of smart manufacturing, this study uses a comprehensive literature review technique for manufacturing sustainability of nanocomposite fabrication for water treatment applications. The model provided will help to create a baseline for AI and hybrid models in the water treatment and wastewater management sectors, allowing for the increased performance and innovative growth. It will serve to provide the framework and give guidance for researchers interested in creating superior nanocomposites for waste and fresh water treatment and management using Industry 4.0. This study looks at a variety of AI approaches as well as how they may be used in water treatment, with an emphasis on pollutant adsorption. This assessment also identified certain obstacles and research gaps in the field of AI applications in water treatment processes.
- Published
- 2022
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- View/download PDF
29. Elettaria cardamomum seed extract synthesized silver nanoparticles for efficient catalytic reduction of toxic dyes
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Muhammad Zahid, Abdul Sattar M. Segar, Shaymaa Al-Majmaie, A.H. Shather, Muhammad Farooq Khan, Arnold C. Alguno, Rey Y. Capangpangan, and Ahmed Ismail
- Subjects
Materials Science (miscellaneous) ,Management, Monitoring, Policy and Law ,Pollution ,Waste Management and Disposal ,Water Science and Technology - Published
- 2023
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30. Morphological, Structural, and Optical Properties of Doped/Codoped ZnO Nanocrystals Film Prepared by Spin Coating Technique and Their Gas Sensing Application
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Neha Verma, Vishal Jagota, null Alimuddin, Arnold C. Alguno, Manik Rakhra, Chanthirasekaran K., and Betty Nokobi Dugbakie
- Subjects
Article Subject ,General Materials Science - Abstract
In today’s world of electronics, nanomaterial applications pose a challenge. The spin coating approach was used to create nanostructured ZnO with wurtzite structure in a recent study. Antimony doping, aluminum, and antimony codoping with 2.0 percent were used to make these films. The impact of doped and codoped films on structural, optical properties, and morphological has been examined using a variety of characterization approaches. A ZnO nanocrystal with a diameter of 20-30 nm was discovered using XRD (X-ray diffraction). According to SEM (scanning electron microscope) scans, the grain size is in the 80-120 nm region. The use of Fourier transform infrared spectroscopy (FTIR) to detect elemental elements was studied, and the peak at 400-520 cm-1 was identified as ZnO. The optical properties of doped and codoped ZnO were checked, and it was discovered that antimony-doped ZnO has a larger band gap than Al and antimony-codoped ZnO. This proved that ZnO may be used in gas sensors and solar cells. The gas response of a static gas sensor system based on Sb-doped films was measured and compared to Al- and Sb-codoped films in the presence of ethanol vapor.
- Published
- 2022
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31. Characterization of Fabricated Gold-Doped ZnO Nanospheres and Their Use as a Photocatalyst in the Degradation of DR-31 Dye
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Neha Verma, Vishal Jagota, Arnold C. Alguno, null Alimuddin, Manik Rakhra, Pawan Kumar, and Betty Nokobi Dugbakie
- Subjects
Article Subject ,General Materials Science - Abstract
Water contamination is a significant issue in the modern day, caused by the textile dying business, and it has a detrimental impact on living organisms. We report on the manufacture of gold-doped ZnO nanospheres using a simple heat treatment approach and the use of ZnO nanoparticles as photocatalysts for the degradation of methyl orange dye. To increase this degrading activity, Au was utilised as a modifier, and their temperature quenching effect was noticed. One of the most efficient electron grabbers in the conduction band is Au ion. The novelty of this recent research is that it has found that anatase to rutile phase transformation is promoted, and the highest transformation was achieved by using 1.0% of Au, which proves Au-doped ZnO-based nanoparticles are best for this degradation of dyes. The structural, morphological, optical, electrical, and photocatalytic characteristics of the synthesised nanocatalysts were determined. These nanoparticles have a grain size of 45-75 nm. Photocatalytic activity was investigated using UV-Vis spectra, and a significant absorption peak of about 482 nm was discovered. With increasing frequency, the dielectric constant and frequency of the produced nanoparticles drop. The kinetic analysis yields a rate constant of 0.0165 min-1 for nanosphere-like particles. At a concentration of 1% Au, the produced nanoparticles degrade the dye completely in 150 minutes when exposed to UV light.
- Published
- 2022
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32. Identification and Classification of Depressed Mental State for End-User over Social Media
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Akhilesh Kumar, Anuradha Thakare, Manisha Bhende, Amit Kumar Sinha, Arnold C. Alguno, and Yekula Prasanna Kumar
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Article Subject ,General Computer Science ,InformationSystems_INFORMATIONINTERFACESANDPRESENTATION(e.g.,HCI) ,General Mathematics ,General Neuroscience ,Emotions ,Humans ,ComputingMilieux_COMPUTERSANDSOCIETY ,Linguistics ,General Medicine ,Students ,Social Media ,Semantics - Abstract
In researching social network data and depression, it is often necessary to manually label depressed and non-depressed users, which is time-consuming and labor-intensive. The aim of this study is that it explores the relationship between social network data and depression. It can also contribute to detecting and identifying depression. Through collecting and analyzing college students’ microblog social data, a preliminary screening algorithm for college students’ suspected depression microblogs based on depression keywords, and semantic expansion is researched; a comprehensive lexical grammar was proposed. This research provided has a preliminary screening method based on depression keywords and semantic expansion for college students’ suspected depression microblogs, with a screening accuracy. This method forms a depression keyword table by constructing the basic keyword table and the semantic expansion based on the word embedding learning model Word2Vec. Finally, the word table is used to calculate the semantic similarity of the tested microblogs and then identify whether it is a suspected depression microblog. The experimental results on the microblog dataset of college students show that the comprehensive lexical method is better than the SDS questionnaire segmentation method and the expert lexical method in terms of screening accuracy; the comprehensive lexical approach can quickly and automatically screen out a tiny proportion of suspected doubts from a large number of college students’ microblogs. Depression Weibo can reduce the workload of experts’ annotation, improve annotation efficiency, and provide a suitable data processing basis for the subsequent accurate identification (classification problem) of patients with depression.
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- 2022
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33. Comparison and evaluation of the performance of graphene-based biosensors
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Walid Kamal Abdelbasset, Saade Abdalkareem Jasim, Dmitry Olegovich Bokov, Maria Sergeevna Oleneva, Anvar Islamov, Ali Thaeer Hammid, Yasser Fakri Mustafa, Ghulam Yasin, Arnold C. Alguno, and Ehsan Kianfar
- Subjects
Inorganic Chemistry ,Renewable Energy, Sustainability and the Environment ,Process Chemistry and Technology ,Organic Chemistry ,Materials Chemistry ,Ceramics and Composites ,Energy Engineering and Power Technology - Published
- 2022
- Full Text
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34. Improvised centrifugal spinning for the production of polystyrene microfibers from waste expanded polystyrene foam and its potential application for oil adsorption
- Author
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Felmer S. Latayada, Marco Laurence M. Budlayan, Rey Y. Capangpangan, Antonio Basilio, Susan D. Arco, Arnold C. Alguno, Jonathan N. Patricio, and Jeanne Phyre Lagare-Oracion
- Subjects
business.product_category ,Materials science ,Scanning electron microscope ,General Engineering ,Engineering (General). Civil engineering (General) ,Contact angle ,chemistry.chemical_compound ,Adsorption ,chemistry ,Chemical engineering ,Oil adsorption ,Microfiber ,Polystyrene microfiber ,Expanded polystyrene foam ,Fiber ,Polystyrene ,Fourier transform infrared spectroscopy ,TA1-2040 ,business ,Spinning ,Centrifugal spinning - Abstract
A straightforward approach to recycle waste expanded polystyrene (EPS) foam to produce polystyrene (PS) microfibers using the improvised centrifugal spinning technique is demonstrated in this work. A typical benchtop centrifuge was improvised and used as a centrifugal spinning device. The obtained PS microfibers were characterized for their potential application for oil adsorption. Fourier transform infrared spectroscopy results revealed similarity on the transmission bands of EPS foam and PS microfibers suggesting the preservation of the EPS foam’s chemical composition after the centrifugal spinning process. Scanning electron microscopy displayed well-defined fibers with an average diameter of 3.14 ± 0.59 μm. At the same time, energy dispersive X-ray spectroscopy revealed the presence of carbon and oxygen as the primary components of the fibers. Contact angle (θCA) measurements showed the more enhanced hydrophobicity of the PS microfiber (θCA = 100.2 ± 1.3°) compared to the untreated EPS foam (θCA = 92.9 ± 3.5°). The PS microfiber also displayed better oleophilicity compared to EPS foam. Finally, the fabricated PS microfibers demonstrated promising potential for oil removal in water with a calculated sorption capacity value of about 15.5 g/g even at a very short contact time. The fabricated PS fiber from the waste EPS foam may provide valuable insights into the valorization of polymeric waste materials for environmental and other related applications.
- Published
- 2021
35. Effects of N-Octadecane as PCM on the Thermal and Mechanical Properties of Polyurethane Foams Utilizing Coconut-Based Polyols
- Author
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Miceh Rose D. Magdadaro, Rey Y. Capangpangan, Arnold A. Lubguban, and Arnold C. Alguno
- Abstract
The utilization of vegetable oil in producing bio-based polyol, as an alternative replacement to petroleum-based polyol in making polyurethane (PU) foam has gained a lot of interest due to its finite supply and low production cost. In this study, bio-based polyol using coconut oil as raw material produced PU foam as thermal insulation material. The vegetable oil-based polyol was prepared using a two-step method, while PU foams were prepared by the free-rise method. In order to enhance the thermal properties of the produce PU foams, phase change material (PCM) was added to the PU foam formulation. FTIR spectra result showed peaks at 2920 cm-1 and 2850-1, which signifies the CH2 asymmetric stretching, indicating that n-octadecane was successfully incorporated into PU foams. Moreover, heat flow meter (HFM) and thermo-gravimetric analysis (TGA) show PU foam with 1% n-octadecane shows better thermal properties than other produced PU foams. Furthermore, the universal testing machine (UTM) result shows an enhancement in the mechanical properties of the produced PU foam. These results demonstrate that the addition of n-octadecane to the PU foam formulation improved the mechanical properties of PU foams while enhancing their thermal properties.
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- 2022
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36. Photocatalytic Activity of Cellulose Nanocrystals/Zinc Oxide Nanocomposite Against Thiazine Dye under UV and Visible Light Irradiation
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Rey Marc T. Cumba, Clark B. Ligalig, Jhea Mae D. Tingson, Meralin P. Molina, Arnold C. Alguno, Custer C. Deocaris, Felmer Latayada, Indah Primadona, Rey Yonson Capangpangan, DOST-PCIEERD (Project No. 08905), and MSU-Naawan and Caraga State University
- Subjects
General Chemical Engineering ,Nanocomposite, Photodegradation, Cellulose Nanocrystals, Methylene Blue, Photocatalyst - Abstract
Organic dyes used in the food and textile industries are the primary sources of environmental contamination due to their high toxicity and nonbiodegradability. This paper describes the synthesis of cellulose nanocrystals/zinc oxide (CNC/ZnO) nanocomposite via the sol-gel method. Various characterization techniques such as FTIR spectroscopy, UV-Vis spectroscopy, and FESEM-EDX analysis were done. FTIR and UV-Vis analyses initially confirmed the formation of CNC/ZnO nanocomposites. FESEM-EDX showed a fiber-like structure with agglomerated particles on the CNC-ZnO image, suggesting the functionalization of ZnO nanoparticles onto the CNC. The photocatalytic potential of the CNC/ZnO nanocomposite was then evaluated by degrading 10 ppm thiazine dye (methylene blue) solution. The solution was irradiated with UV and visible light at an ambient temperature. The degradation was monitored at different time intervals using a UV spectrophotometer to measure the absorbance value intermittently. Results on the photocatalytic activity indicated that the synthesized CNC/ZnO nanocomposite showed faster degradation under UV light irradiation than the visible light, with an efficiency of 96.11% and 85.60%, respectively, after 180 mins of light irradiation. Further, the results suggest that the synthesized CNC/ZnO nanocomposite showed great promise as a sustainable material for the degradation of organic contaminants in an aqueous solution.
- Published
- 2022
37. Effects of precursor concentration on the properties of magnetic iron oxide nanoparticles synthesized using brown seaweed (Sargassum crassifolium) extract
- Author
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Rey Y. Capangpangan, Marco Laurence M. Budlayan, Jonathan N. Patricio, Susan D. Arco, and Arnold C. Alguno
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010302 applied physics ,Thermogravimetric analysis ,Nanostructure ,Materials science ,Scanning electron microscope ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Absorbance ,Crystallinity ,chemistry.chemical_compound ,chemistry ,Dynamic light scattering ,0103 physical sciences ,Thermal stability ,0210 nano-technology ,Iron oxide nanoparticles ,Nuclear chemistry - Abstract
This work reports the influence of precursor concentration on the thermal and optical properties of magnetic iron oxide nanoparticles (MIONPs) synthesized via the green synthesis route. A brown seaweed (Sargassum crassifolium) extract was used to mediate the reduction of iron precursors. Ultraviolet–visible spectra showed a sharp peak between 315 and 375 nm, which corresponds to the absorbance of MIONPs. This peak intensified with an increasing concentration of iron precursors. The Fourier transform infrared spectra revealed the presence of the transmittance bands around 557 cm−1 and 565 cm−1, which corresponds to Fe-O-Fe vibrational modes suggesting the successful formation of iron oxide nanoparticles. The dynamic light scattering technique revealed that the average hydrodynamic size of the MIONPs was 31.96 ± 15.61 nm and 147.40 ± 28.48 nm. Atomic force micrograph and scanning electron micrograph both showed quasi-spherical nanostructures with sizes ranging from 40 to 215 nm. Furthermore, X-ray diffraction and thermogravimetric analyses revealed the crystallinity and thermal stability of the synthesized MIONPs, respectively. This investigation on the effect of precursor concentration provides a valuable insight for the green- mediated synthesis of MIONPs that is vital for various environmental, biomedical, and industrial application.
- Published
- 2021
- Full Text
- View/download PDF
38. Influence of cellulose fibers extracted from pineapple (Ananas comosus) leaf to the mechanical properties of rigid polyurethane foam
- Author
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Rey Y. Capangpangan, Jessalyn C. Grumo, Arnold C. Alguno, Lady Jaharah Y. Jabber, and Arnold A. Lubguban
- Subjects
010302 applied physics ,Materials science ,biology ,Scanning electron microscope ,02 engineering and technology ,021001 nanoscience & nanotechnology ,biology.organism_classification ,01 natural sciences ,chemistry.chemical_compound ,Cellulose fiber ,Compressive strength ,chemistry ,Chemical engineering ,0103 physical sciences ,Lignin ,Hemicellulose ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Ananas ,Polyurethane - Abstract
The influence of cellulose fibers extracted from pineapple (Ananas comosus) leaf fibers on polyurethane foam’s mechanical properties (PUF) is reported. The PUFs were reinforced with different weight ratios (1, 3, and 5 wt%) of cellulose fibers. The surface morphology of the extracted cellulose fibers was determined using a scanning electron microscope (SEM). The functional groups and vibrational modes of the reinforced PUFs were measured using Fourier transform infrared spectroscopy (FTIR). The influence of cellulose fibers to the density and mechanical property of the PUFs were also investigated using universal testing Machine (UTM). Experimental results showed the absence of hemicellulose, lignin, and other soluble materials present in the pineapple leaves after alkaline treatment, suggesting high-quality cellulose fibers. Likewise, FTIR spectra revealed the presence of typical urethane linkages of PUFs suggesting the successful formation of PUFs with a varied amount of cellulose fibers. The mechanical properties of the PUFs with an increasing amount of cellulose fibers exhibit a decrease of the compressive strength of the fabricated PUFs may be due to the lack of cross-linking between the cellulose fibers and PUFs that will influence the reactivity in the system that eventually affects the polyurethane foam density expansion.
- Published
- 2021
- Full Text
- View/download PDF
39. Design and fabrication of a low-cost curcumin-based paper sensor for rapid 'naked-eye' cyanide sensing
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Rey Y. Capangpangan, Custer C. Deocaris, Jeanne Phyre L. Oracion, Lyka B. De La Rosa, Mark Anthony M. Lavapiez, Arnold C. Alguno, and Regielyn R. Paden
- Subjects
010302 applied physics ,Analyte ,Aqueous solution ,biology ,Filter paper ,Cyanide ,02 engineering and technology ,021001 nanoscience & nanotechnology ,biology.organism_classification ,01 natural sciences ,chemistry.chemical_compound ,chemistry ,0103 physical sciences ,Curcumin ,Naked eye ,Curcuma ,0210 nano-technology ,Spectroscopy ,Nuclear chemistry - Abstract
Cyanide ( CN - ) is a deleterious chemical and can cause serious health effects upon exposure even at low concentrations. Different sensors have been developed to monitor cyanide in water, which, however, suffers from complex mechanisms and high-cost. Curcuma longa or turmeric is a commercially available natural dye (usually in powder form) used as medicine. The phenolic substance curcumin is responsible for its yellow color and is capable of sensing environmentally significant analytes such as CN - . In this study, a colorimetric sensor for cyanide in aqueous solution was fabricated by the immobilization of crude curcumin on ordinary filter paper. The curcumin was extracted from locally available turmeric powder using a simple extraction method. Its successful integration in the filter paper was validated by FT-IR spectroscopy. UV–Vis analysis showed that the curcumin-based paper sensor was sensitive to CN - (down to 5.0 ppm), producing a visual change from yellow to dark red. The fabricated sensor also demonstrated high selectivity towards CN - in the presence of N a + , K + , and F - . Its response time was found to be inversely proportional to the concentration of the CN - in the solution. Assessment of reusability revealed that the sensor was reusable for up 8 cycles before significant changes in colorimetric response were observed. Importantly, the fabricated sensor exhibited applicability for actual cyanide monitoring in real water samples.
- Published
- 2021
- Full Text
- View/download PDF
40. Synthesis and characterization of Fe3O4/BiOCl/Cu2O composite as photocatalyst for the degradation of organic dyes
- Author
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Lyka B. De La Rosa, Custer C. Deocaris, Rey Y. Capangpangan, Kristian Dave O. Licayan, Arnold C. Alguno, Jonathan P. Manigo, and Jeanne Phyre L. Oracion
- Subjects
010302 applied physics ,Chemistry ,Composite number ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Absorbance ,chemistry.chemical_compound ,0103 physical sciences ,Photocatalysis ,Methyl orange ,Degradation (geology) ,0210 nano-technology ,Spectroscopy ,Methylene blue ,Visible spectrum ,Nuclear chemistry - Abstract
Increasing anthropogenic and industrial activities lead to the contamination of aquatic resources with organic pollutants such as dyes. In this work, a magnetic composite photocatalyst composed of Fe3O4, BiOCl, and Cu2O was fabricated for the degradation of organic dye pollutants. The composite was synthesized via a simple co-precipitation method. FT-IR and SEM-EDX analyses confirmed the formation of Fe3O4/BiOCI/Cu2O (FBC) composite. Photocatalytic degradation was tested under UV, and visible light using model organic dyes, methyl orange (MO), and methylene blue (MB), and was monitored using UV–Vis spectroscopy. The absorbance was found to decrease corresponding to the reduction of dye concentration during photocatalytic degradation. A plot of absorbance versus irradiation time for both model dyes exhibited exponential decay; faster degradation was observed with MO than with MB. Furthermore, the degradation of both dyes using the FBC photocatalyst was more efficient under UV light.
- Published
- 2021
- Full Text
- View/download PDF
41. High thermoelectric power factor of Sr doped Bi2Te3 thin film through energy filtering effect
- Author
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Arslan Ashfaq, Michael M. Sabugaa, Mongi Ben Moussa, N. Almousa, Elsammani Ali Shokralla, Rey Y. Capangpangan, Arnold C. Alguno, Md Amzad Hossain, Abdulaziz M. Alanazi, and Mohamed Abboud
- Subjects
General Chemical Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics - Published
- 2023
- Full Text
- View/download PDF
42. Recognition of Protein Network for Bioinformatics Knowledge Analysis Using Support Vector Machine
- Author
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Arshpreet Kaur, Abhijit Chitre, Kirti Wanjale, Pankaj Kumar, Shahajan Miah, and Arnold C. Alguno
- Subjects
Support Vector Machine ,Article Subject ,General Immunology and Microbiology ,Wavelet Analysis ,Computational Biology ,Proteins ,General Medicine ,General Biochemistry, Genetics and Molecular Biology ,Protein Structure, Secondary - Abstract
Protein is the material foundation of living things, and it directly takes part in and runs the process of living things itself. Predicting protein complexes helps us understand the structure and function of complexes, and it is an important foundation for studying how cells work. Genome-wide protein interaction (PPI) data is growing as high-throughput experiments become more common. The aim of this research is that it provides a dual-tree complex wavelet transform which is used to find out about the structure of proteins. It also identifies the secondary structure of protein network. Many computer-based methods for predicting protein complexes have also been developed in the field. Identifying the secondary structure of a protein is very important when you are studying protein characteristics and properties. This is how the protein sequence is added to the distance matrix. The scope of this research is that it can confidently predict certain protein complexes rapidly, which compensates for shortcomings in biological research. The three-dimensional coordinates of C atom are used to do this. According to the texture information in the distance matrix, the matrix is broken down into four levels by the double-tree complex wavelet transform because it has four levels. The subband energy and standard deviation in different directions are taken, and then, the two-dimensional feature vector is used to show the secondary structure features of the protein in a way that is easy to understand. Then, the KNN and SVM classifiers are used to classify the features that were found. Experiments show that a new feature called a dual-tree complex wavelet can improve the texture granularity and directionality of the traditional feature extraction method, which is called secondary structure.
- Published
- 2022
43. Homogeneous Decision Community Extraction Based on End-User Mental Behavior on Social Media
- Author
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Suneet Gupta, Sumit Kumar, Sunil L. Bangare, Shibili Nuhmani, Arnold C. Alguno, and Issah Abubakari Samori
- Subjects
General Computer Science ,Article Subject ,General Mathematics ,General Neuroscience ,Decision Making ,Humans ,General Medicine ,Social Media ,Algorithms ,Language - Abstract
Aiming at the inadequacy of the group decision-making method with the current attribute value as interval language information, an interval binary semantic decision-making method is proposed, which considers the decision maker’s psychological behavior. The scope of this research is that this paper is based on localized amplification method. The localized amplification method used in this research may amplify physiological movement after removing unwanted noise, allowing the movement trend to be seen with the naked eye, improving the CNN network’s mental identification accuracy. These two algorithms analyze the input picture from various perspectives, allowing the CNN network to extract more information and enhance identification accuracy. A new distance formula with interval binary semantics closer to decision-makers thinking habits is defined; time degree is introduced. An optimization model is established to solve the time series weights by considering the comprehensive consistency of expert evaluation. Based on prospect theory, a prospect deviation value is constructed and minimized weight optimization model, using the interactive multiple attribute decision community making (TODIM) method based on the new distance measure to calculate the total overall dominance of the schemes to rank the schemes. Taking the selection and evaluation of supply chain collaboration partners as an example, the effectiveness and rationality of the proposed method are verified.
- Published
- 2022
44. Prediction of Rockfill Materials' Shear Strength Using Various Kernel Function-Based Regression Models-A Comparative Perspective
- Author
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Mahmood Ahmad, Ramez A. Al-Mansob, Irfan Jamil, Mohammad A. Al-Zubi, Mohanad Muayad Sabri Sabri, and Arnold C. Alguno
- Subjects
shear strength ,rockfill materials ,Gaussian functions ,polynomial kernel ,radial basis function ,Pearson universal kernel ,General Materials Science - Abstract
The mechanical behavior of the rockfill materials (RFMs) used in a dam’s shell must be evaluated for the safe and cost-effective design of embankment dams. However, the characterization of RFMs with specific reference to shear strength is challenging and costly, as the materials may contain particles larger than 500 mm in diameter. This study explores the potential of various kernel function-based Gaussian process regression (GPR) models to predict the shear strength of RFMs. A total of 165 datasets compiled from the literature were selected to train and test the proposed models. Comparing the developed models based on the GPR method shows that the superlative model was the Pearson universal kernel (PUK) model with an R-squared (R2) of 0.9806, a correlation coefficient (r) of 0.9903, a mean absolute error (MAE) of 0.0646 MPa, a root mean square error (RMSE) of 0.0965 MPa, a relative absolute error (RAE) of 13.0776%, and a root relative squared error (RRSE) of 14.6311% in the training phase, while it performed equally well in the testing phase, with R2 = 0.9455, r = 0.9724, MAE = 0.1048 MPa, RMSE = 0.1443 MPa, RAE = 21.8554%, and RRSE = 23.6865%. The prediction results of the GPR-PUK model are found to be more accurate and are in good agreement with the actual shear strength of RFMs, thus verifying the feasibility and effectiveness of the model.
- Published
- 2022
45. Analyzing Characteristics for Two-Step SET Operation Scheme for Improving Write Time in Nanoscale Phase-Change Memory (PCM)
- Author
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Milad Mohseni, Ahmed Alkhayyat, P. Balaji Srikaanth, Ali Jawad Alrubaie, Arnold C. Alguno, Rey Y. Capangpangan, and Bhupesh Kumar Singh
- Subjects
Article Subject ,General Materials Science - Abstract
PCM (phase-change memory) is a memory innovation that has gained prominence as a capacity-class memory for computer systems. It is made up of a tiny functional amount of phase-change material that is located in the middle of two electrodes. In PCM, data is kept by utilizing the difference in electrical resistance between a crystalline phase, which has a high resistance, and its amorphous phase, which has a low resistance. Using electrical pulses, the phase-change material would be shifted from a high to the low conductive region and conversely. However, the device’s material science concerned with PCM has been generally studied, and questions remain regarding their electrical, warm, and fundamental aspects since its publication in the 1960s. One major downside of PCM is its low heat conductivity, which causes delays in the energy charging/discharging procedure and hardware efficiency. As a result of this, one of the primary focuses of PCM studies has been the improvement of PCM’s heat conductivity through the utilization of nanotechnology and nanomaterials. Nanotechnology has been developing ultrasmall nanoparticles to improve traditional PCMs’ thermophysical characteristics. These nanomaterials, such as metal, metal oxide, and carbon, will significantly boost PCM’s thermal properties, including supercooling, viscosity, and heat capacity. An overview of PCM devices is presented in this article, which underlies perusing and composition activities. Consequently, we offered novel PCM devices and materials. Therefore, the total study is qualitative, and no machine learning approach is used. Because of this, we cannot say that the data is quantitative. Our work includes both test representations of the specific features observed in nanoscale PCM devices and material science demonstrations. In the end, we provide a point of view on some remaining open inquiries and possible future exploration directions.
- Published
- 2022
- Full Text
- View/download PDF
46. Ag modified ZnO microsphere synthesis for efficient sonophotocatalytic degradation of organic pollutants and CO2 conversion
- Author
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Muhammad Farooq Khan, Syed ul Hasnain Bakhtiar, Amir Zada, Fazal Raziq, Hassan Anwar Saleemi, Muhammad Shahzeb Khan, Pir Muhammad Ismail, Arnold C. Alguno, Rey Y. Capangpangan, Asad Ali, Salman Hayat, Sharafat Ali, Ahmed Ismail, and Muhammad Zahid
- Subjects
Materials Science (miscellaneous) ,Management, Monitoring, Policy and Law ,Pollution ,Waste Management and Disposal ,Water Science and Technology - Published
- 2022
- Full Text
- View/download PDF
47. Bio-based Foam Sorbents : For Oil Spill Cleanups
- Author
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Arnold A. Lubguban, Roberto M. Malaluan, Gerard G. Dumancas, Arnold C. Alguno, Arnold A. Lubguban, Roberto M. Malaluan, Gerard G. Dumancas, and Arnold C. Alguno
- Subjects
- Surfaces (Physics), Biomaterials, Bioremediation, Biophysics, Membranes (Biology)
- Abstract
This book highlights the advantages of using sorbents in oil spill cleanup while dealing with the challenges of limited capacity and disposal. Bio-based foam sorbents are new but promising sorbents to oil spill cleanup. They are environmentally friendly materials derived from renewable resources such as vegetable oil and biomass, designed to absorb or adsorb oil and other pollutants from water, coastal areas, wetlands, ice-covered waters, and urban surfaces. These foams offer a sustainable alternative to traditional petroleum-based sorbents, with comparable or even superior performance in oil adsorption capacity, recyclability, and biodegradability. Moreover, a bio-based foam sorbent with inherent hydrophobic property is discussed, opening a new pathway for bio-based foam sorbents that usually need surface modification. This book is a good read for environmental scientists, engineers, sustainability experts, and researchers offering insights in related to the chemistry, performance, and commercialization potential of bio-based foam sorbents. It explores various methods for synthesizing bio-based foam sorbents, providing a detailed examination of the underlying chemistry involved in these processes.
- Published
- 2025
48. Facile Synthesis and Characterization of Magnetic Nanophotocatalyst for Photocatalytic Degradation of Cyanide
- Author
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Joel H. Jorolan, Jeanne Phyre B. Lagare, Rey Y. Capangpangan, Mark Anthony M. Lavapiez, and Arnold C. Alguno
- Subjects
Cyanide degradation ,Materials science ,Nanocomposite ,Cyanide ,010401 analytical chemistry ,010501 environmental sciences ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Characterization (materials science) ,chemistry.chemical_compound ,chemistry ,Photocatalysis ,General Materials Science ,Photocatalytic degradation ,0105 earth and related environmental sciences ,Nuclear chemistry - Abstract
This paper reports on the synthesis and application of Fe3O4/TiO2 nanocomposite. In situ attachment of TiO2 coating to the surface of the magnetic nanoparticles (Fe3O4) was attained by direct condensation of titanium precursors. Characterization result suggests that the average particle size of the synthesized nanocomposite is 10-15 nm. Also, FT-IR result confirms the presence of TiO2 layer in the surface of the magnetic nanoparticles. Furthermore, the prepared Fe3O4/TiO2 nanocomposite was utilized as an active magnetic nanophotocatalyst for the degradation of cyanide. Results show that even at 5.0 mg of Fe3O4/TiO2 photocatalyst, higher cyanide removal efficiency (91%) was obtained when 60 ppm CN- was incubated with the photocatalyst for 30 minutes. Likewise, it has been demonstrated that the synthesized magnetic nanophotocatalyst can be used to degrade cyanide using sunlight as the natural light source. A 94% cyanide removal efficiency was obtained when the sample was incubated with the synthesized magnetic nanophotocatalyst for 120 minutes under sunlight irradiation. Importantly, the prepared magnetic photocatalyst can be re-used several times (up to 5 cycles) without significant changes in the cyanide removal efficiency.
- Published
- 2019
- Full Text
- View/download PDF
49. Controlling the Growth of Zinc Oxide/ Polyaniline Nanocomposites on Platinum-Coated Substrate for Possible Solar Cell Applications
- Author
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Rey Y. Capangpangan, Reynaldo M. Vequizo, Blessie A. Basilia, Bernabe L. Linog, Arnold C. Alguno, Katherine M. Emphasis, and Melchor J. Potestas
- Subjects
010302 applied physics ,Materials science ,Nanocomposite ,Band gap ,Substrate (chemistry) ,chemistry.chemical_element ,02 engineering and technology ,Zinc ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,law.invention ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,0103 physical sciences ,Polyaniline ,Solar cell ,General Materials Science ,0210 nano-technology ,Platinum - Abstract
We report on the growth of zinc oxide/polyaniline (ZnO/PANI) nanocomposites deposited on platinum (Pt)–coated glass substrate via chemical bath deposition and dip–casting technique is reported. Scanning electron micrographs of the nanocomposites revealed that etching of ZnO nanorods takes place during growth which turn into plate–like and distorted nanostructures. We found out that increasing the concentration of NH4OH triggered increase in nanostructure diameter. The surface morphology of nanocomposites significantly changed as the molar concentration of NH4OH precursor varies. Fast fourier transform infrared spectroscopy results showed the interaction of ZnO and PANI by observing the shift of peaks to the higher wavenumbers. The measured optical band gap of the nanocomposites are in good aggreement with the reported values. This result indicates that the grown ZnO/PANI nanocomposites is a good material for solar cell device.
- Published
- 2019
- Full Text
- View/download PDF
50. Antibacterial Activities of Zinc Oxide Nanostructures with Different Structures
- Author
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Bernabe L. Linog, Arnold C. Alguno, Rolen Brian P. Rivera, Rey Y. Capangpangan, Melchor J. Potestas, Ma. Reina Suzette B. Madamba, and Blessie A. Basilia
- Subjects
Materials science ,Nanostructure ,chemistry.chemical_element ,Nanotechnology ,02 engineering and technology ,Zinc ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,chemistry ,General Materials Science ,0210 nano-technology - Abstract
We report on antibacterial activities of Zinc oxide (ZnO) with different structures. Fast furrier transform infrared spectroscopy ZnO nanostructures showed peaks in the range between 450–600 cm-1 indicating the successful growth through the presence of Zn-O stretching. On the other hand, impurities such as zinc complexes might be present due to the appearance of peaks at 1110 cm-1, 1390 cm-1 and 1506 cm-1. Furthermore, SEM images revealed that nanorods and sea-urchin like nanostructures are present in the produced ZnO nanostructures. Nanorods exhibit a better antibacterial response than the sea-urchin like structure. The change in structural morphology along with its purity has greatly influenced the area of bacterial inhibition zone during antibacterial testing.
- Published
- 2019
- Full Text
- View/download PDF
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