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Thickness, Annealing, and Surface Roughness Effect on Magnetic and Significant Properties of Co40Fe40B10Dy10 Thin Films

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materials 2023年第17期16卷 5995页

作者： Liu, Wen-Jen Chang, Yung-Huang Chiang, Chia-Chin Chen, Yuan-Tsung Wang, Yu-Zhi Wu, Chueh-Lin Lin, Shih-Hung Ou, Sin-Liang Department of Materials Science and Engineering I-Shou University Kaohsiung84001 Taiwan Bachelor Program in Industrial Technology National Yunlin University of Science and Technology 123 University Road Section 3 Douliou64002 Taiwan Department of Mechanical Engineering National Kaohsiung University of Science and Technology Kaohsiung80778 Taiwan Graduate School of Materials Science National Yunlin University of Science and Technology 123 University Road Section 3 Douliou64002 Taiwan Department of Electronic Engineering National Yunlin University of Science and Technology 123 University Road Section 3 Douliou64002 Taiwan Bachelor Program for Design and Materials for Medical Equipment and Devices Da-Yeh University Changhua51591 Taiwan

In this study, Co40Fe40B10Dy10 thin films were deposited using a direct current (DC) magnetron sputtering technique. The films were deposited on glass substrates with thicknesses of 10, 20, 30, 40, and 50 nm, and heat-treated in a vacuum annealing furnace at 100, 200, and 300 °C. Various instruments were used to examine and analyze the effects of roughness on the magnetic, adhesive, and mechanical properties. From the low frequency alternating current magnetic susceptibility (χac) results, the optimum resonance frequency is 50 Hz, and the maximum χac value tends to increase with the increase in the thicknesses and annealing temperatures. The maximum χac value is 0.18 at a film thickness of 50 nm and an annealing temperature of 300 °C. From the four-point probe, it is found that the resistivity and sheet resistance values decrease with the increase in film deposition thicknesses and higher annealing temperatures. From the magnetic force microscopy (MFM), the stripe-like magnetic domain distribution is more obvious with the increase in annealing temperature. According to the contact angle data, at the same annealing temperature, the contact angle decreases as the thickness increases due to changes in surface morphology. The maximal surface energy value at 300 °C is 34.71 mJ/mm2. The transmittance decreases with increasing film thickness, while the absorption intensity is inversely proportional to the transmittance, implying that the thickness effect suppresses the photon signal. Smoother roughness has less domain pinning, more carrier conductivity, and less light scattering, resulting in superior magnetic, electrical, adhesive, and optical performance. © 2023 by the authors.

关键词： Thin films

Centrifugal Spinning of Porous Polylactic Acid Fibers by Centrifugal Spinning with Phase Separation for Oil Removal Application

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SSRN 2024年

作者： Negoro, Masaki Doan, Hoan Ngoc Vo, Phu Phong Khuat, Khanh Van Thi Kinashi, Kenji Sakai, Wataru Tsutsumi, Naoto Master’s Program of Innovative Materials Kyoto Institute of Technology Matsugasaki Sakyo Kyoto606-8585 Japan Tissue Engineering and Regenerative Medicine Laboratory School of Biomedical Engineering International University Vietnam National University Ho Chi Minh City Viet Nam Faculty of Chemistry University of Science Ho Chi Minh City Viet Nam Doctor’s Program of Materials Chemistry Graduate School of Science and Technology Kyoto Institute of Technology Matsugasaki Sakyo Kyoto606-8585 Japan Faculty of Materials Science and Engineering Kyoto Institute of Technology Matsugasaki Sakyo Kyoto606-8585 Japan

Developing biodegradable oil absorption fibrous materials is essential because discarding conventional separation materials could cause secondary pollution due to their nondegradable properties. In this study, highly hydrophobic and superoleophilic porous polylactic acid (PLA) fibers were prepared using centrifugal spinning combined with nonsolvent-induced phase separation. The porous structure of PLA fibers was controlled by the ratio between good solvent and nonsolvent in the spinning solutions. The morphology and physical properties of the obtained PLA fibers were investigated using various measurement techniques. The PLA fibrous membrane prepared from a PLA solution containing chloroform/dimethylformamide (80/20 w/w) indicated not only a high water contact angle but also a high oil sorption value. The porous PLA fibers are a potential candidate for use as green materials for environmental applications. © 2024, The Authors. All rights reserved.

关键词： Spinning (fibers)

Effect of Fe on the Photo/Piezocatalytic Activity of Bazr1-2xfe2xo3-Δ Ceramics

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SSRN 2023年

作者： Fernandes, Daiane Hernandes, Paola Gay Moreira, Mario Lucio Raubach, Cristiane Wienke Jardim, Pedro Lovato Gomes Ferrer, Mateus Meneghetti Moreira, Eduardo Ceretta Mastelaro, Valmor Roberto Cava, Sergio da S. Post-Graduate Program in Materials Science and Engineering Federal University of Pelotas RS Pelotas96010-610 Brazil Post-Graduate Program in Physics Federal University of Pelotas RS Capão do Leão96160-000 Brazil Spectroscopy Laboratory Federal University of Pampa RS Bagé96413-172 Brazil Physics Institute São Paulo University SP São Carlos13560-970 Brazil

BaZr1-2xFe2xO3-δ (x=0.00, 0.02, 0.04 and 0.08) samples were prepared by microwave-assisted hydrothermal method quickly and at low-temperature. Furthermore, we explored for the first time the effect of iron (Fe) in the barium zirconate (BZO) lattice on photocatalytic and piezocatalytic activity to degrade organic dye. Fe insertion reduced the band gap, altered the electronic structure and induced luminescence quenching. The catalytic activity of the samples was analyzed through the degradation of the rhodamine B (RhB) dye. The photocatalytic experiment was performed under UVC light and the piezocatalytic experiment under ultrasonic vibration. The pure sample of BZO showed better photocatalytic performance, while the insertion of Fe was unfavorable to degrade RhB. In contrast, pure BZO has negligible piezocatalytic activity, but a low Fe content is highly beneficial for promoting piezocatalysis. Based on the findings, this study provides important information for obtaining effective photocatalysts and piezocatalysts to be used in environmental remediation. © 2023, The Authors. All rights reserved.

关键词： Iron

Effect of Fe on the Photo/Piezocatalytic Activity of Bazr1-2xfe2xo3-Δ Ceramics

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SSRN 2023年

作者： Fernandes, Daiane Hernandes, Paola Gay Moreira, Mario Lucio Raubach, Cristiane Wienke Gomes Jardim, Pedro Lovato Ferrer, Mateus Meneghetti Moreira, Eduardo Ceretta Mastelaro, Valmor Roberto Cava, Sergio da S. Post-Graduate Program in Materials Science and Engineering Federal University of Pelotas RS Pelotas96010-610 Brazil Post-Graduate Program in Physics Federal University of Pelotas RS Capão do Leão96160-000 Brazil Spectroscopy Laboratory Federal University of Pampa RS Bagé96413-172 Brazil Physics Institute São Paulo University SP São Carlos13560-970 Brazil

关键词： Temperature

Microwave-Assisted Synthesis of Triphenyl Amine-Based Phenyl Quinazolines: Investigation of Photophysical and Fluorescence Switching Behavior

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SSRN 2024年

作者： Selvam, Pravinkumar Kumar, Ashok S.K. Manjappa, Kiran B. Department of Chemistry School of Advanced Sciences Vellore Institute of Technology Tamil Nadu Vellore632014 India Graduate Program for Biomedical and Materials Science College of Science Tunghai University No. 1727 Sec. 4 Taiwan Boulevard Xitun District Taichung407224 Taiwan

Microwave-assisted synthesis and photophysical properties of triphenylamine-cored di (P1) and tri (P2) quinazolines are reported herewith. Probes P1 and P2 exhibited positive solvatochromism when the solvent polarity increased from toluene to DMSO. Interestingly, the probes were found to be sensitive towards volatile organic acids and bases, such as trifluoroacetic acid (TFA) and triethyl amine (TEA), leading to reversible switching behavior in the solution state. When TFA is added, the probes become colorless and non-fluorescent due to controlled protonation. However, gradual neutralization of the protonated probes with TEA restores their characteristic color and fluorescence. The photophysical and protonation mechanisms were studied through DFT/TD-DFT calculations. The controlled acid-base switching behaviors of the prepared probes P1 and P2 portray them as potential candidates for functional applications. © 2024, The Authors. All rights reserved.

关键词： Probes

Nonsaturated large magnetoresistance and transport dynamics in a n-doped cryogenic WSe2 field-effect device

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Physical Review B 2025年第12期111卷 125307-125307页

作者： Wei-Chen Lin Ching-Chen Yeh Jia-Zhu Zou Nhat Anh Nguyen Phan Inayat Uddin Hai Yen Le Thi Kenji Watanabe Takashi Taniguchi Gil-Ho Kim Department of Engineering and System Science National Tsing Hua University Hsinchu 300 Taiwan Taiwan International Graduate Program Academia Sinica Taipei 115 Taiwan Department of Physics National Taiwan University Taipei 106 Taiwan Department of Electrical and Computer Engineering Sungkyunkwan University (SKKU) Suwon 164 Republic of Korea Sungkyunkwan Advanced Institute of Nano Technology (SAINT) Sungkyunkwan University (SKKU) Suwon 16419 Republic of Korea Research Center for Electronic and Optical Materials National Institute for Materials Science 1-1 Namiki Tsukuba 305-0044 Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science 1-1 Namiki Tsukuba 305-0044 Japan

Interest in the two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs) continues to intensify, driven by their suitable band gaps to supplant silicon as next-generation semiconductor materials. Among various TMDs, tungsten diselenide (WSe2) is renowned for its superior electrical properties in carrier density and mobility under ambient conditions. Despite its notable attributes, the behavior of monolayer WSe2 in the electron-doped regime under cryogenic conditions remains largely uncharted, particularly concerning its magnetotransport properties. In this study, we reveal the transport mechanisms of monolayer WSe2 from high temperatures down to the cryogenic regime. As evident by Efros–Shklovskii variable-range hopping (E-S VRH) in the cryogenic regime, strong Coulomb interactions arise between electrons. Above 8 K, an uncommon nonsaturated quadratic large magnetoresistance (MR) can be explained by the wave-function shrinkage model, which is consistent with the E-S VRH transport mechanism. Notably, the nonsaturated quadratic large MR shows a magnitude up to 1740% at 13 T. These findings underscore the potential applications for monolayer WSe2 in cryogenic field-effect devices, magnetic sensors, and memory devices and mark a significant advance in magnetotransport research.

关键词： Monolayers

Plasma Surface Treatment of Cocr and Nicr Alloys for Dental Applications: A Comparative Study of Tin Thin Film Plasma Deposition Techniques

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SSRN 2024年

作者： Balica, Naasson Matheus Pereira Almeida, Larissa Solano Rossino, Luciana Sgarbi Pupim, Denise Monção, Renan Matos Costa, Thércio Henrique de Carvalho Santos, Rafaela Luiz Pereira Sousa, Rômulo Ribeiro Magalhães Nunes, Lívio César Cunha Federal University of Piauí Technology Center Graduate Program in Materials Science and Engineering Avenida Universitária s/n Ininga PI Teresina Brazil Federal University of São Carlos Graduate Program in Materials Science SP Sorocaba Brazil University of São Paulo Ribeirão Preto School of Dentistry Avenida do Café SP Ribeirão Preto Brazil Federal University of Rio Grande do Norte Technology Center Department of Mechanical Engineering University Campus Natal RN Lagoa Nova Brazil

Cobalt-chromium and nickel-chromium metal alloys have been widely used as biomaterials in the dental field due to their excellent physical-mechanical properties and biocompatibility, as well as the low cost of the material. However, in unfavorable environments, such as the oral cavity, these dental prostheses composed of these alloys can suffer alterations in their structure where they can undergo rapid changes with the surface corrosion process, which can vary with pH and temperature, typically related to changes in the patient's diet. The aim of this work is to carry out a comparative study between the cathodic cage (CC) and hollow cathode (HC) methods, in which a plasma deposition treatment of titanium nitride (TiN) thin films was carried out on CoCr and NiCr samples, in order to subsequently evaluate their surface characteristics and tribological properties in relation to each method. The samples were characterized using X-ray diffractometry (XRD), scanning electron microscopy (SEM/EDS) and micro abrasive wear tests on each sample from the three groups of alloys mentioned. It was observed that the TiN films provided greater resistance to the wear mechanism of all the samples, where through the characterizations, it can be inferred that the two types of treatments carried out on the samples are suitable for dental applications. © 2024, The Authors. All rights reserved.

关键词： Chromium alloys

An Efficient Three-Factor Authenticated Key Agreement Technique Using FCM Under HC-IoT Architectures

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Computers, materials & Continua 2022年第7期72卷 1373-1389页

作者： Chandrashekhar Meshram Agbotiname Lucky Imoize Sajjad Shaukat Jamal Parkash Tambare Adel R.Alharbi Iqtadar Hussain Department of Post Graduate Studies and Research in Mathematics Jayawanti Haksar Government Post-Graduation CollegeCollege of Chhindwara UniversityBetul460001M.P.India Department of Electrical and Electronics Engineering Faculty of EngineeringUniversity of LagosAkokaLagos100213Nigeria Department of Electrical Engineering and Information Technology Institute of Digital CommunicationRuhr University44801BochumGermany Department of Mathematics College of ScienceKing Khalid UniversityAbhaSaudi Arabia Water Resources&Applied Mathematics Research Lab Nagpur440027India College of Computing and Information Technology University of TabukTabuk71491Saudi Arabia Mathematics Program Department of MathematicsStatistics and PhysicsCollege of Arts and SciencesQatar University2713DohaQatar

The Human-Centered Internet of Things(HC-IoT)is fast becoming a hotbed of security and privacy *** users can establish a common session key through a trusted server over an open communication channel using a three-party authenticated key *** of the early authenticated key agreement systems relied on pairing,hashing,or modular exponentiation processes that are computationally intensive and *** order to address this problem,this paper offers a new three-party authenticated key agreement technique based on fractional chaotic *** new scheme uses fractional chaotic maps and supports the dynamic sensing of HC-IoT devices in the network architecture without a password *** projected security scheme utilized a hash function,which works well for the resource-limited HC-IoT *** results show that our new technique is resistant to password guessing attacks since it does not use a ***,our approach provides users with comprehensive privacy protection,ensuring that a user forgery attack causes no ***,our new technique offers better security features than the techniques currently available in the literature.

关键词： Three-party authenticated key agreement anonymity fractional chaotic maps Chebyshev polynomial password table human-centered internet of things(HC-IoT)

Thermodynamic and Environmental Assessment of Low-GWP Alternative Refrigerants for Domestic Cooling

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Journal of The Institution of Engineers (India): Series C 2023年第2期104卷 377-383页

作者： Islam, Md. Amirul Rupam, Tahmid Hasan Hosan, Shahadat Saha, Bidyut Baran Institute for Materials Chemistry and Engineering Kyushu University Kasuga-Koen 6-1 Kasuga-Shi Fukuoka816-8580 Japan Department of Electrical and Electronics Engineering Bangabandhu Sheikh Mujibur Rahman Science and Technology University Gopalganj8100 Bangladesh Kyushu University 744 Motooka Nishi-Ku Fukuoka819-0395 Japan Kyushu University Program for Leading Graduate School Green Asia Education Center Kyushu University Fukuoka Japan Department of Mechanical Engineering Kyushu University 744 Motooka Nishi-Ku Fukuoka819-0395 Japan

Nearly two billion air-conditioning (AC) units are currently being used for space cooling worldwide. The majority of these ACs use R134a as the working fluid, a greenhouse gas (GHG) with a global warming potential (GWP) of 1300 kg-CO2-eq. According to the rules set by the world environment safety organizations, the GWP of domestic air-conditioning systems must not exceed 750 kg-CO2-eq. Hence, the R134a must be phased out by 2025, and an alternative refrigerant with similar thermodynamic properties yet low GWP is required. Therefore, the authors have investigated several potential binary/ternary refrigerant blends in this study. Among the studied refrigerants, R445A, R30A, and NPB2 (newly proposed blend: 8% R152a + 92% R1234yf) can reduce 90–99% global warming impact (more than 200 million tonnes of CO2 emission equivalent) caused by the domestic air-conditioning systems every year. © 2023, The Institution of Engineers (India).

关键词： Refrigerants