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Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra S.Castro-Lopes J.Matilla-Arias Idglan S.de Lima Edson C.Silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

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Effect of proteases on water-soluble and fat-soluble aroma precursors of goat visceras protein hydrolysate

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Food Bioscience 2022年第3期47卷 975-985页

作者： Ana Rita Ribeiro de Araújo Cordeiro Lorena Lucena de Medeiros Lary de Souza Olegário Leila Moreira de Carvalho Taliana Kenia Alencar Bezerra Maria Teresa Bertoldo Pacheco Mércia de Sousa Galvão Marta Suely Madruga Post Graduate Program in Food Science and Technology Department of Food EngineeringTechnology CentreFederal University of ParaibaCampus I58051-900João PessoaParaíbaBrazil Food Technology Institute (ITAL).Science and Food Quality Center 13070-179CampinasSão PauloBrazil

This study investigated the action of proteolytic enzymes in the production of goat viscera hydrolysates,and their flavoring *** study focus the production of flavor precursor molecules and the formation of volatile compounds resulting from four hydrolysis treatments:HA-Alcalase®,HF-Flavourzyme®,HN-Neutrase®,and HFN-Flavourzyme® and Neutrase®.The highest degree of hydrolysis (26.74%),number (23 volatiles) and concentration of volatile compounds (274.0 μg/L) were obtained with the action of *** main classes of volatile compounds identified in hydrolysates included acids,aldehydes,pyrazines,terpenes and Streacker *** acids,sugars and fatty acids were identified with higher concentrations in HF and HFN hydrolysates due to the low participation of these precursors in the formation of volatile ***,the use of Alcalase in the proteolysis of goat viscera stood out compared to other enzymes,providing impacting aroma compounds,such as pyrazines,for meat flavor.

关键词： Aroma precursors Flavoring Goat byproducts Proteases Enzymatic hydrolysates Volatile compounds

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Characterizations of Ni-loaded lignite char catalysts and their performance enhancements to catalytic steam gasification of coal

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Journal of the Energy Institute 2022年 105卷 53-71页

作者： Tipo, Ronnachai Tippayawong, Nakorn Chaichana, Chatchawan Chimupala, Yothin Chaiklangmuang, Suparin Graduate Program in Industrial Chemistry Faculty of Science Chiang Mai University Chiang Mai50200 Thailand Department of Industrial Chemistry Faculty of Science Chiang Mai University Chiang Mai50200 Thailand Department of Mechanical Engineering Faculty of Engineering Chiang Mai University Chiang50200 Thailand Center of Excellence in Materials Science and Technology Faculty of Science Chiang Mai University Chiang Mai50200 Thailand Materials Science Research Center Faculty of Science Chiang Mai University Chiang Mai50200 Thailand

Catalyst characteristics such as specific surface area, porosity and active site play an essential role in catalyst design. Understanding of the characteristic functions in controlling catalyst activity is necessary for considering the catalyst application, especially the Ni-loaded lignite char catalyst, employed in catalytic steam gasification. In this work, the unmodified and five modified catalysts were used to study the effect of catalyst characteristics on their performance for catalytic steam gasification of coal in the two-stage fixed-bed reactor. The findings indicated that the fresh acid modified catalysts increased specific surface area and micropore formation, including the smaller Ni metal crystallite size, the decreasing of Ni metal nanoparticle size and the well-dispersed of Ni metal nanoparticles. Meanwhile, the fresh modified catalysts by the alkali and the combined alkali-acid treatments promoted mesopore formation. Enhancing catalytic steam gasification of coal, it was found that the mesoporosity of catalyst was the considerable initial characteristic for controlling the catalyst activity. The total gas yields of the mesoporous catalysts were in the range of 50.65–77.70 mmol/gVM,feed, while the total gas yields of the microporous catalysts were 43.82–55.34 mmol/gVM,feed. After catalyst testings, the specific surface areas and number of mesopores in the spent catalysts were increased by steam. Remarkably, these changing pore sizes affected the transformations of the isotherms (type I + II to type II) and the hysteresis loops (type H4 to type H3). Also, steam influenced the conversion of Ni metals to NiO, Ni(OH)2 and Ni2O3. For thermal property, all spent catalysts had high thermal stability. The modified catalysts could decrease carbon deposition more than the unmodified catalyst, which was an upside for catalyst reusability. © 2022 Energy Institute

关键词： Catalyst activity

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Numerical evaluation of the pressure drop in multiphase flow of the catenary riser with the presence of leakage

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Defect and Diffusion Forum 2016年 366卷 157-165页

作者： De Almeida Tavares, Daniela Passos Simões Sarmento, Lígia Rafaely Barbosa Barbosa, Enivaldo Santos De Farias Neto, Severino Rodrigues De Lima, Antonio Gilson Barbosa Federal University of Campina Grande Center of Science and Technology Post Graduate Program in Chemical Engineering Campina GrandeParaíba58429-900 Brazil Federal University of Campina Grande Center of Science and Technology Petroleum Engineering Department Campina GrandeParaíba58429-900 Brazil Federal University of Campina Grande Center of Science and Technology Mechanical Engineering Department Campina GrandeParaíba58429-900 Brazil

The growing demand for oil brings the need for discovery of deeper reservoirs, especially of ultra-deepwater reservoirs. Thus, production in marine systems using components such as risers (flexible or rigid pipes) has been the focus of many studies in different areas. These ducts are used in the transportation of multiphase fluids (oil, water and gas) produced from the oil well located on the seabed to the platform surface. Due to the extreme conditions present in the offshore fields of production, the equipments that transport produced fluids operate close to their limits. So eventually, the flexible pipes may have structural integrity faults like leaks, which can cause production losses, accidents with victims and environmental disasters. The leak depends of a number of properties or parameters measured at the site of the leak, for example, integrity of the pipe material, release of fluids and noise emission characteristics or manifestation of some other type of signal behavior, variation of pressure drops close to the leak, among others. There are a variety of techniques available for detecting leaks, among which there is the mathematical modeling approach using computational techniques. In this context, this paper aims to study the fluid dynamics of a transient multiphase flow in a catenary riser in the presence of leakage. Herein a 3D Eulerian-Eulerian model was applied, including the turbulent model (RNG k-ϵ), using the commercial package ANSYS CFX® 15 to perform all simulations. The numerical results of velocity, volume fraction and pressure of the involved phases are presented and discussed. © 2016 Trans Tech Publications.

关键词： Drops

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Corrigendum to "Extracellular vesicles from human adipose-derived stem cell spheroids: Characterization and therapeutic implications in diabetic wound healing" [Mater. Today Bio Volume 29, December 2024, 101333](S2590006424003946)(10.1016/***.2024.101333)

Materials Today Bio

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materials Today Bio 2025年

作者： Quiñones, Edgar Daniel Wang, Mu-Hui Liu, Kuan-Ting Lu, Ting-Yu Lan, Guan-Yu Lin, Yu-Ting Chen, Yu-Liang Shen, Tang-Long Wu, Pei-Hsun Hsiao, Yu-Sheng Chuang, Er-Yuan Yu, Jiashing Cheng, Nai-Chen Taiwan International Graduate Program Sustainable Chemical Science & Technology Academia Sinica Institute of Chemistry Taipei115 Taiwan Department of Surgery National Taiwan University Hospital and College of Medicine Taipei100 Taiwan Department of Chemical Engineering National Taiwan University Taipei10617 Taiwan Program in Materials Science and Engineering University of California San Diego CA92093 United States Department of Plant Pathology & Microbiology National Taiwan University Taiwan Johns Hopkins Institute for NanoBioTechnology John Hopkins University Baltimore MD21218 United States Department of Materials Science and Engineering National Taiwan University of Science and Technology Taipei106 Taiwan School of Biomedical Engineering Taipei Medical University Taipei11031 Taiwan Research Center for Developmental Biology and Regenerative Medicine National Taiwan University Taipei Taiwan

The authors regret that the selected Figure 2A, depicting cell sheets and spheroids, was previously published in Stem Cell Research & Therapy (2022;13:276. https://***/10.1186/s13287-022-02948-3). This duplication was an unintentional oversight, as the image was included solely for illustrative purposes and does not contribute to any quantitative analysis. We sincerely apologize for this mistake and propose the following corrections: 1. Replacing Figure 2A with a new image as below that does not overlap with our previously published work.2. Including a correction statement clarifying that the image serves only an illustrative function and does not affect the study's quantitative ***, we have identified an error in Section 3.3 of the text, where "SEM" should be corrected to "TEM." We appreciate your consideration of these revisions and apologize for any confusion caused. The authors would like to apologize for any inconvenience caused. Your sincerely, Jiashing Yu and Nai-Chen Cheng Fixed Figure 2A[Figure presented] © 2025 The Author(s)

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Synthesis and characterization of a nanostructured matrix of hydrated calcium phosphate 59th

Synthesis and characterization of a nanostructured matrix of...

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59th Brazilian Ceramic Conference, CBC 59

作者： Possamai, Maicon Douglas Camargo, Nelson Heriberto Almeida Floriano-Silva, Daiara Eckstein, Marli Baltazar Roesler Franczak, Priscila Ferraz Universidade do Estado de Santa Catarina UDESC Post-Graduate Materials Science and Engineering PPGCEM Paulo Malschitzki s/n. Zona Industrial Norte JoinvilleSC Brazil

ISBN: (纸本)9783035711158

Bone reconstruction biomaterials are topics of interest in dentistry, orthopedics, scientific, commercial. The most popular bone repairing and reconstruction biomaterials are calcium phosphates. The demand for biomaterials is associated with the chemical and crystallographic characteristics of the human bone apatite. The wet synthesis method is common in the production of nanostructured powders of hydrated calcium phosphates, providing nanoparticles with sizes less than 50nm. This study aimed to synthesize and characterize hydrated calcium phosphate powders in the molar ratio of Ca/P = 1.67. After calcination at temperature 900°C/2h, these powders provide nanostructured hydroxyapatite matrix. The characterization studies were performed with Scanning Electron Microscopy, X-rays diffraction and Infrared Spectroscopy by Fourier Transform. The results show that the synthesis method provides hydrated calcium phosphate powders formed by aggregated and agglomerated nanoparticles. The thermal treatment of hydrated calcium phosphate powder led to formation of hydroxyapatite matrix. © 2017 Trans Tech Publications, Switzerland.

关键词： Synthesis (chemical)

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Recycling Of PP/LDPE blend: Miscibility, thermal properties, rheological behavior and crystal structure 74

Recycling Of PP/LDPE blend: Miscibility, thermal properties,...

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74th Annual Technical Conference and Exhibition of the Society of Plastics Engineers, SPE ANTEC Indianapolis 2016

作者： Aumnate, Chuanchom Spicker, Claudia Kiesel, Raphael Samadi, Majid Rudolph, Natalie Mechanical Engineering Department Polymer Engineering Center University of Wisconsin-Madison WI United States Textile Science Department of Design Studies and Materials Science Graduate Program University of Wisconsin-Madison WI United States

ISBN: (纸本)9780692719619

Blending of plastics used in packaging is an interesting approach for recycling or upcycling. Therefore, this study focused on the effects of processing on the properties of recycled PP and PP/LDPE blends. MFI measurements, Differential Scanning Calorimetry (DSC) and hot-stage polarized optical microscopy techniques were used to investigate the miscibility of PP/LDPE blends based on the thermal properties, degree of crystallinity, crystallization and morphology development in the blends. The MFI indicates, that PP and PP/LDPE blends are marginally sensitive to degradation at common processing conditions. The degree of crystallinity of the blends decreases with an increase of the LDPE content. Furthermore, the spherulite growth rate and crystal size of PP decrease with an increase of LDPE content. The shifts of crystallization temperatures from the DSC measurement, in conjunction with the crystallization kinetics, indicate that PP/LDPE (25 wt% LDPE) is partially miscible.

关键词： Crystal structure

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Porphyrin-Grafted Poly(ethylene terephthalate) as a Reusable and Highly Selective Colorimetric Probe for Mercuric Ion Contaminants in Aqueous Samples

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ACS Applied materials and Interfaces 2024年第30期16卷 39195-39205页

作者： Atayde, Eduardo C. Takenaka, Yasumasa Abe, Hideki Wu, Ming-Rou Wu, Kevin C.-W. Molecular Science and Technology Program Taiwan International Graduate Program Academia Sinica Department of Chemistry National Tsing Hua University Department of Chemical Engineering National Taiwan University Bioplastic Research Team RIKEN Center for Sustainable Resource Science Department of Chemical Engineering and Materials Science Yuan Ze University Department of Chemical Engineering Chung Yuan Christian University

Heavy metals are the most hazardous water pollutants, with severe health and environmental consequences. Among these, mercuric (Hg2+) ions are known to cause detrimental health issues in both humans and aquatic life. ... 详细信息

Heavy metals are the most hazardous water pollutants, with severe health and environmental consequences. Among these, mercuric (Hg²⁺) ions are known to cause detrimental health issues in both humans and aquatic life. Due to this, several analytical techniques have been devised to detect and quantify the amount of this ion. However, most of these require advanced instrumentation, prolonged analysis time, and sample preparation. In this study, a low-cost and highly reusable colorimetric probe was developed by grafting porphyrin to poly(ethylene terephthalate) sheets using an oxazoline polymer as covalent adhesive. Upon exposure to trace amounts of Hg²⁺ in solution, the fabricated material visually transitioned from faint brownish pink to green by the complexation mechanism. Additionally, the transparency of this probe allowed the quantitative spectrophotometric determination of the Hg²⁺ concentration in aqueous samples. It was also shown that the material is highly stable, which can be reused for more than 50 times without significant decline in its performance, hence, making it suitable for the onsite monitoring of mercuric ion contamination in different bodies of water. © 2024 The Authors. Published by American Chemical Society.

关键词： colorimetric probe mercuric ion oxazoline PET porphyrin

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Terahertz phonon polariton concentrator based on perovskite oxides

Terahertz phonon polariton concentrator based on perovskite ...

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2023 Conference on Lasers and Electro-Optics, CLEO 2023

作者： Xu, Rui Lin, Tong Luo, Jiaming Chen, Xiaotong Blackert, Elizabeth R. Moon, Alyssa R. JeBailey, Khalil M. Zhu, Hanyu Department of Materials Science and Nano Engineering Rice University Houston United States Applied Physics Graduate Program Rice University Houston United States Program Rice University Houston United States

ISBN: (纸本)9781957171258

We report the experimental demonstration of surface phonon-polaritonic devices in a broad spectral range of 7-13 THz based on SrTiO3. We designed planar ultrafast concentrators that amplifies transient electric field by 6 times and measured an average field of 0.5 GV/m in an optically resolvable area in the far field. © 2023 The Author(s)

关键词： Perovskite

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Detailed assessment of partial thermodynamic quantities of tin in molten Bi-Sn alloys from electromotive force measurements

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Metallurgical Transactions B 1990年第1期21卷 87-96页

作者： Cho, Seung-Am Camisotti, Roberto Vélez, Mariano H. Graduate Program of Metallurgy and Materials Science Venezuelan Institute of Scientific Research (IVIC) Caracas 1020A Apartado 21827 Venezuela School of Metallurgical Engineering and Materials Science Central University of Venezuela Caracas 1050A Apartado 50361 Venezuela Conduven Company Caracas Venezuela Department of Materials Science and Engineering Massachusetts Institute of Technology Cambridge 02139 MA United States

All the partial thermodynamic quantities, including the activity and activity coefficient of tin, a Sn and γSn, in the liquid Bi-Sn alloys between 300 °C and 500 °C are assessed in detail from electromotive...

All the partial thermodynamic quantities, including the activity and activity coefficient of tin, a_Sn and γ_Sn, in the liquid Bi-Sn alloys between 300 °C and 500 °C are assessed in detail from electromotive force (emf) data. The emf values were obtained from a modified molten salt electrolyte concentration cell that had extraordinary stability within +0.005 mV. The composition dependence of γ_Sn did not follow Darken's quadratic formalism, nor did the alloy behave as a regular solution. The excess partial quantities, Δ-H_Sn, Δ-S_Sn^xs, and Δ-G_Sn^xs, are oscillating across the composition, and the activity curve exhibits double, positive and negative, deviations from Raoult's law. The a_Sn, γ_Sn, and Δ-G_Sn^xs change from positive to negative departure from ideality in the tin-rich region beyond about x_Sn = 0.82. All those partial quantities and γ_Sn^o, including the β° (the α function of tin) at infinite dilution, are determined accurately by means of Chiotti's method. © 1990 The Minerals, Metals & Material Society.

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