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Ariponnammal S, Shalini S, Anusha S. Tailoring Room Temperature Ferromagnetism and Observation of Electrolyte of Widest Potential Window in Gd
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Se Nano Particles. CRYSTAL RESEARCH AND TECHNOLOGY 2022. [DOI: 10.1002/crat.202200106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- S. Ariponnammal
- Department of Physics Gandhigram Rural Institute, Deemed To Be University Dindigul District Gandhigram Tamilnadu 624302 India
| | - S. Shalini
- Department of Physics Gandhigram Rural Institute, Deemed To Be University Dindigul District Gandhigram Tamilnadu 624302 India
| | - S. Anusha
- Department of Physics Gandhigram Rural Institute, Deemed To Be University Dindigul District Gandhigram Tamilnadu 624302 India
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Shahzad K, Mardare CC, Mardare AI, Hassel AW. Growth of mixed anodic films on combinatorial Al-Gd alloys and their superimposed potential-pH diagrams. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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The Critical Behaviour and Magnetism of MnCoGe0.97Al0.03 Compounds. CRYSTALS 2022. [DOI: 10.3390/cryst12020205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
The critical behaviour associated with the field-induced martensitic transformation heavily relies on the vacancy and transition of the magnetic phase in MnCoGe based-compounds. Due to this revelation, an intensive investigation was brought forth to study the substitution of Ge (atomic radius = 1.23 Å) by Al (atomic radius = 1.43 Å) in MnCoGe0.97Al0.03 alloy compound. The room-temperature X-ray diffraction indicated that the reflections were identified with the orthorhombic structure (TiNiSi-type, space group Pnma) and minor hexagonal structure (Ni2In-type, space group P63/mmc). The substitution of Al in the supersession of Ge transmuted the crystal structure from TiNiSi-type to Ni2In-type structure. The MnCoGe0.97Al0.03 compound’s magnetism was driven by interactions that are long in range, as indicated by the study of the critical behaviour in the proximity of TC. The magnetic measurement and neutron diffraction revealed that the structural transition took place with the decrease in temperature. The results from neutron diffraction signify that the transformation of the magnetic field-induced martensitic has a crucial function in producing the immense effect of magnetocaloric systems such as these. This outcome serves a critical function for investigations in the future.
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Isikawa M, Guidelli E. Microfluidic Synthesis of Theranostic Nanoparticles with Near-Infrared Scintillation: Toward Next-Generation Dosimetry in X-ray-Induced Photodynamic Therapy. ACS APPLIED MATERIALS & INTERFACES 2022; 14:324-336. [PMID: 34963048 DOI: 10.1021/acsami.1c20689] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We developed a microfluidic synthesis to grow GdF3:Eu theranostic scintillating nanoparticles to simultaneously monitor the X-ray dose delivered to tumors during treatments with X-ray activated photodynamic therapy (X-PDT). The flow reaction was optimized to enhance scintillation emission from the Eu3+ ions. The as-prepared ∼15 nm rhombohedral-shaped nanoparticles self-assembled into ∼100 nm mesoporous flower-like nanostructures, but the rhombohedral units remained intact and the scintillation spectra unaltered. The conjugation of the ScNPs with multilayers of methylene blue (MB) in a core-shell structure (GdF@MB) resulted in enhanced singlet oxygen (1O2) generation under X-ray irradiation, with maximum 1O2 production for nanoparticles with 4 MB layers (GdF@4MB). High 1O2 yield was further evidenced in cytotoxicity assays, demonstrating complete cell death only for the association of ScNPs with MB and X-rays. Because the scintillating Eu3+ emission at 694 nm is within the therapeutic window and was only partially absorbed by the MB molecules, it was explored for getting in vivo dosimetric information. Using porcine skin and fat to simulate the optical and radiological properties of the human tissues, we showed that the scintillation light can be detected for a tissue layer of ∼16 mm, thick enough to be employed in radiotherapy treatments of breast cancers, for instance. Therefore, the GdF3:Eu ScNPs and the GdF@4MB nanoconjugates are strong candidates for treating cancer with X-PDT while monitoring the treatment and the radiation dose delivered, opening new avenues to develop a next-generation modality of real-time in vivo dosimetry.
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Affiliation(s)
- Mileni Isikawa
- Departamento de Física. FFCLRP- Universidade de São Paulo, Ribeirão Preto, SP 14040-901, Brazil
| | - Eder Guidelli
- Departamento de Física. FFCLRP- Universidade de São Paulo, Ribeirão Preto, SP 14040-901, Brazil
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Lingamdinne LP, Lee S, Choi JS, Lebaka VR, Durbaka VRP, Koduru JR. Potential of the magnetic hollow sphere nanocomposite (graphene oxide-gadolinium oxide) for arsenic removal from real field water and antimicrobial applications. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123882. [PMID: 33254822 DOI: 10.1016/j.jhazmat.2020.123882] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 08/09/2020] [Accepted: 08/31/2020] [Indexed: 06/12/2023]
Abstract
Potential of the magnetic hollow-sphere nanocomposite, graphene oxide-gadolinium oxide (GO-Gd2O3) for arsenic (As) removal from real field water with developing a continuous operating system and antimicrobial activity were investigated. The characterization results suggest that the prepared GO-Gd2O3 is a hallow sphere wool-like nanocomposite having 50.91 m2 g-1 surface area. The sorption studies revealed that a high adsorption capacity (216.70 mg g-1) can be achieved using GO-Gd2O3 (0.1 g L-1) at a pH of 6.0, and temperature of 293 K. The main and novel observations from the loading of Gd2O3 are that the GO adsorption efficiency, adsorbent separation rate from aqueous solutions, and the stability of the composite have been altered. Thus, the developed material can overcome the separation and stability issues associated with the bare GO, and exhibits an enhanced adsorption capacity toward arsenic was higher or comparable with existing magnetic material. In addition, the developed adsorption method was well applied for real field water samples collected from the mining area of South Korea where the GO-Gd2O3 can reduce the quantity of arsenic under the maximum accepted concentration of arsenic considered fit for drinking water stipulated by environmental protection agencies. Furthermore, the GO-Gd2O3 nanocomposite shows a high bacterial photocatalytic inactivation and was comparable with other reports.
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Affiliation(s)
| | - Suhyun Lee
- Department of Environmental Engineering, Kwangwoon University, Seoul, 01897, Republic of Korea
| | - Jong-Soo Choi
- Department of Environmental Engineering, Kwangwoon University, Seoul, 01897, Republic of Korea
| | | | | | - Janardhan Reddy Koduru
- Department of Environmental Engineering, Kwangwoon University, Seoul, 01897, Republic of Korea.
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Zhang J, Kang YM, Shan G, Bobev S. Structural analysis of Gd 6FeBi 2 from single-crystal X-ray diffraction methods and electronic structure calculations. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2019; 75:562-567. [PMID: 31062713 DOI: 10.1107/s2053229619004868] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 04/09/2019] [Indexed: 11/10/2022]
Abstract
The crystal structure of the gadolinium iron bismuthide Gd6FeBi2 has been characterized by single-crystal X-ray diffraction data and analyzed in detail using first-principles calculations. The structure is isotypic with the Zr6CoAl2 structure, which is a variant of the ZrNiAl structure and its binary prototype Fe2P (Pearson code hP9, Wyckoff sequence g f d a). As such, the structure is best viewed as an array of tricapped trigonal prisms of Gd atoms centered alternately by Fe and Bi. The magnetic-ordering temperature of this compound (ca 350 K) is much higher than that of other rare-earth metal-rich phases with the same or related structures. It is also higher than the ordering temperature of many other Gd-rich ternary phases, where the magnetic exchange is typically governed by Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions. First-principles calculations reveal a larger than expected Gd magnetic moment, with the additional contribution arising from the Gd 5d electrons. The electronic structure analysis suggests strong Gd 5d-Fe 3d hybridization to be the cause of this effect, rather than weak interactions between Gd and Bi. These details are of importance for understanding the magnetic response and explaining the high ordering temperature in this material.
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Affiliation(s)
- Jiliang Zhang
- Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul 04620, Republic of Korea
| | - Yong Mook Kang
- Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul 04620, Republic of Korea
| | - Guangcun Shan
- School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing 100083, People's Republic of China
| | - Svilen Bobev
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
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Chun J, Kishore RA, Kumar P, Kang MG, Kang HB, Sanghadasa M, Priya S. Self-Powered Temperature-Mapping Sensors Based on Thermo-Magneto-Electric Generator. ACS APPLIED MATERIALS & INTERFACES 2018; 10:10796-10803. [PMID: 29473409 DOI: 10.1021/acsami.7b17686] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We demonstrate a thermo-magneto-electric generator (TMEG) based on second-order phase transition of soft magnetic materials that provides a promising pathway for scavenging low-grade heat. It takes advantage of the cyclic magnetic forces of attraction and repulsion arising through ferromagnetic-to-paramagnetic phase transition to create mechanical vibrations that are converted into electricity through piezoelectric benders. To enhance the mechanical vibration frequency and thereby the output power of the TMEG, we utilize the nonlinear behavior of piezoelectric cantilevers and enhanced thermal transport through silver (Ag) nanoparticles (NPs) applied on the surface of a soft magnet. This results in large enhancement of the oscillation frequency reaching up to 9 Hz (300% higher compared with that of the prior literature). Optimization of the piezoelectric beam and Ag NP distribution resulted in the realization of nonlinear TMEGs that can generate a high output power of 80 μW across the load resistance of 0.91 MΩ, which is 2200% higher compared with that of the linear TMEG. Using a nonlinear TMEG, we fabricated and evaluated self-powered temperature-mapping sensors for monitoring the thermal variations across the surface. Combined, our results demonstrate that nonlinear TMEGs can provide additional functionality including temperature monitoring, thermal mapping, and powering sensor nodes.
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Affiliation(s)
- Jinsung Chun
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL) , Virginia Polytechnic Institute and State University , Blacksburg , Virginia 24060 , United States
| | - Ravi Anant Kishore
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL) , Virginia Polytechnic Institute and State University , Blacksburg , Virginia 24060 , United States
| | - Prashant Kumar
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL) , Virginia Polytechnic Institute and State University , Blacksburg , Virginia 24060 , United States
| | - Min-Gyu Kang
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL) , Virginia Polytechnic Institute and State University , Blacksburg , Virginia 24060 , United States
| | - Han Byul Kang
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL) , Virginia Polytechnic Institute and State University , Blacksburg , Virginia 24060 , United States
| | - Mohan Sanghadasa
- U.S. Army Aviation and Missile Research, Development, and Engineering Center , Redstone Arsenal , Huntsville , Alabama 35898 , United States
| | - Shashank Priya
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL) , Virginia Polytechnic Institute and State University , Blacksburg , Virginia 24060 , United States
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Chun J, Song HC, Kang MG, Kang HB, Kishore RA, Priya S. Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System. Sci Rep 2017; 7:41383. [PMID: 28145516 PMCID: PMC5286423 DOI: 10.1038/srep41383] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 12/20/2016] [Indexed: 11/22/2022] Open
Abstract
Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer.
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Affiliation(s)
- Jinsung Chun
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL), Virginia Tech, VA 24060, USA
| | - Hyun-Cheol Song
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL), Virginia Tech, VA 24060, USA
| | - Min-Gyu Kang
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL), Virginia Tech, VA 24060, USA
| | - Han Byul Kang
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL), Virginia Tech, VA 24060, USA
| | - Ravi Anant Kishore
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL), Virginia Tech, VA 24060, USA
| | - Shashank Priya
- Center for Energy Harvesting Materials and System (CEHMS), Bio-Inspired Materials and Devices Laboratory (BMDL), Virginia Tech, VA 24060, USA
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Magnetic ordering temperature of nanocrystalline Gd: enhancement of magnetic interactions via hydrogenation-induced "negative" pressure. Sci Rep 2016; 6:22553. [PMID: 26931775 PMCID: PMC4773832 DOI: 10.1038/srep22553] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 02/16/2016] [Indexed: 11/17/2022] Open
Abstract
Gadolinium is a nearly ideal soft-magnetic material. However, one cannot take advantage of its properties at temperatures higher than the room temperature where Gd loses the ferromagnetic ordering. By using high-purity bulk samples with grains ~200 nm in size, we present proof-of-concept measurements of an increased Curie point (TC) and spontaneous magnetization in Gd due to hydrogenation. From first-principles we explain increase of TC in pure Gd due to the addition of hydrogen. We show that the interplay of the characteristic features in the electronic structure of the conduction band at the Fermi level in the high-temperature paramagnetic phase of Gd and “negative” pressure exerted by hydrogen are responsible for the observed effect.
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Ferdinand A, Probst AC, Michels A, Birringer R, Kaul SN. Critical behaviour of nanocrystalline gadolinium: evidence for random uniaxial dipolar universality class. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:056003. [PMID: 24444664 DOI: 10.1088/0953-8984/26/5/056003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on how nanocrystal size affects the critical behaviour of the rare-earth metal Gd near the ferromagnetic-to-paramagnetic phase transition. The asymptotic critical behaviour of the coarse-grained polycrystalline sample (with an average crystallite size of L≅100 μm) is that of a (pure) uniaxial dipolar ferromagnet, as is the case with single crystal Gd, albeit the width of the asymptotic critical region (ACR) is reduced. As the grain size approaches ∼30 nm, the ACR is so narrow that it could not be accessed in the present experiments. Inaccessibly narrow ACR for L ∼ 30 nm and continuous increase in the width of the ACR as L decreases from 16 to 9.5 nm basically reflect a crossover to the random uniaxial dipolar fixed point caused by the quenched random exchange disorder prevalent at the internal interfaces (grain boundaries).
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Affiliation(s)
- A Ferdinand
- Experimentalphysik, Universität des Saarlandes, D-66041 Saarbrücken, Germany
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Arumugam S, Manivannan N, Murugeswari A. Simple uniaxial pressure device for ac-susceptibility measurements suitable for closed cycle refrigerator system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:063906. [PMID: 17614625 DOI: 10.1063/1.2745726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A simple design of the uniaxial pressure device for the measurement of ac-susceptibility at low temperatures using closed cycle refrigerator system is presented for the first time. This device consists of disc micrometer, spring holder attachment, uniaxial pressure cell, and the ac-susceptibility coil wound on stycast bobbin. It can work under pressure till 0.5 GPa and at the temperature range of 30-300 K. The performance of the system at ambient pressure is tested and calibrated with standard paramagnetic salts [Gd(2)O(3), Er(2)O(3), and Fe(NH(4)SO(4))(2)6H(2)O], Fe(3)O(4), Gd metal, Dy metal, superconductor (YBa(2)Cu(3)O(7)), manganite (La(1.85)Ba(0.15)MnO(3)), and spin glass material (Pr(0.8)Sr(0.2)MnO(3)). The performance of the uniaxial pressure device is demonstrated by investigating the uniaxial pressure dependence of La(1.85)Ba(0.15)MnO(3) single crystal with P||c axis. The Curie temperature (T(c)) decreases as a function of pressure with P||c axis (dT(c)dP(||c axis)=-11.65 KGPa) up to 46 MPa. The design is simple, is user friendly, and does not require pressure calibration. Measurement can even be made on thin and small size oriented crystals. The failure of the coil is remote under uniaxial pressure. The present setup can be used as a multipurpose uniaxial pressure device for the measurement of Hall effect and thermoelectric power with a small modification in the pressure cell.
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Affiliation(s)
- S Arumugam
- High Pressure Low Temperature Lab, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, India.
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chapter 4 Spontaneous Magnetoelastic Effects in Gadolinium Compounds. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1567-2719(09)60008-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Affiliation(s)
- K. A. Gschneidner
- Ames Laboratory and Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011-3020; e-mail:
| | - V. K. Pecharsky
- Ames Laboratory and Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011-3020; e-mail:
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