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Publication Metadata only Oxidative thermal conversion of hydrothermal derived precursors toward the mixed-metal cobaltite spinel oxides (Znco2o4 and nico2o4): In-situ investigation by synchrotron-radiation xrd and xas techniques(2021-10-01) Wanchai Deeloed; Yuranan Hanlumyuang; Wanwisa Limphirat; Songwut Suramitr; Kantapat Chansaenpak; Pongsakorn Kanjanaboos; Suttipong Wannapaiboon; Worawat Wattanathana; Kasetsart University; Mahidol University; Thailand National Science and Technology Development Agency; Synchrotron Light Research InstituteIn-situ investigations of structural transitions during the thermal-oxidative event of mixedmetal spinel oxide precursors, the so-called nickel-(NCO) and zinc-containing (ZCO) cobaltite spinel precursors, were investigated to understand... the formations of the derived NiCo2O4 and ZnCo2O4 spinel oxides, respectively. In-situ XRD investigation revealed that emerged temperatures for spinel oxide phase were between 325 and 400◦C, depending on the cationic substituent. It indicated that the emergedPublication Metadata only NiAl 2 O 4 spinel-type catalysts for deoxygenation of palm oil to green diesel(2018-08-01) Atthapon Srifa; Rungnapa Kaewmeesri; Cheng Fang; Vorranutch Itthibenchapong; Kajornsak Faungnawakij; Mahidol University; King Mongkut s University of Technology Thonburi; Thailand National Science and Technology Development Agency© 2018 Elsevier B.V. NiAl 2 O 4 spinel-type catalyst was successfully prepared by an incipient wetness impregnation method accompanied with high-temperature calcination at 1273 K for 10 h. The effect of reduction temperatures (773, 923, and 1073 K... degree at different temperatures. The TEM analysis revealed the formation of large particle size of the catalysts reduced at higher temperature. The highest product yield (94.3%) was achieved for the NiAl 2 O 4 reduced at 923 K. Interestingly, the spinelPublication Metadata only An improved mean field theory for mixed spinel ferrites(1995-09-02) I. M. Tang; S. Varamit; Mahidol UniversityThe standard mean field approach neglects the random disordering of magnetic and nonmagnetic ions with the sublattice of the mixed spinel ferrites. It is known that this disordering can lead to real effects. A mean field theory is developed in whichPublication Metadata only A molecular field theory for inverse spinel ferrite(1979-04-16) I. Ming Tang; Chomkwan Prayoonwech; Mahidol University; Faculty of ScienceA molecular field theory is developed for inverse spinel ferrites which takes into account the disorder arising from the random arrangement of two types of magnetic ions in the B sublattice. It is seen that the disorder gives rise to a localPublication Metadata only Local field fluctuations in the mixed spinel ferrite, Ni1-xZnxFe2O4(1999-03-20) I. M. Tang; S. Varamit; B. Wiwatanapataphee; Mahidol University; The Institute of Science and Technology for Research and Development, Mahidol UniversityThe magnetic properties of the mixed spinel ferrites Ni1-xZnxFe2O4 are studied with the framework of a mean field approach which takes into account the effects of random arrangements of the Zn and Fe ions in the A-sublattice and of the Ni and FePublication Metadata only Enhancement of photocatalytic by Mn3O4 spinel ferrite decorated graphene oxide nanocomposites(2021-06-01) Tanawat Imboon; Jeerawan Khumphon; Khrongkhwan Yotkuna; I. Ming Tang; Sirikanjana Thongmee; Kasetsart University; Mahidol Universitybands from 250 to 550 nm. These bands arise from the d–d crystal field transitions of the tetrahedral Mn3+ species and indicate a distortion in the crystal structure. Photo-catalytic activity of spinel ferrite Mn3O4 NP’s by themselves was low but photo... with an interplanar d-spacing of 0.49 nm for (101) plane.2.Photocatalytic activity of spinel ferrite Mn3O4 nanoparticles by itself is low.3.Number of photoelectrons created depends on number of Mn3O4 on a given area of GO4.The bonding of the Mn3O4 to the GO sheetPublication Metadata only Encapsulation of a powdery spinel-type Li+ion sieve derived from biogenic manganese oxide in alginate beads(2016-11-01) Paulmanickam Koilraj; Siwaporn Meejoo Smith; Qianqian Yu; Sarah Ulrich; Keiko Sasaki; Kyushu University; Mahidol University; Virginia Polytechnic Institute and State University© 2016 Elsevier B.V. A powdery lithium ion sieve (HMO) derived from biogenic birnessite was homogeneously integrated in sodium alginate (AL) beads. The composite beads were then characterized and their Li+adsorption properties were investigated. Scanning electron microscopy–energy dispersive spectroscopy analysis showed that the HMO particles were homogeneously dispersed in the AL beads even after drying. The adsorption isotherm of Li+adsorption to HMO encapsulated in AL beads (HMO–AL) was well fitted by the linear Langmuir model, and the beads showed a maximum adsorption capacity of 3.61 mmol/g based on HMO, which is comparable with the value of the original powdery HMO. Kinetic studies revealed that adsorption of Li+follows a pseudo-second-order model with rate constant k2 = 2.8–11.9 × 10− 3 g/(mmol min) for the initial Li+concentration range 2.56–4.23 mM. Diffusion of Li+from aqueous solution to the HMO particle through the Ca–AL network is the rate-limiting step for Li+adsorption to HMO–AL beads. The HMO-AL beads enhanced the handling efficiency for Li+adsorption and reused without significant reduction of Li+adsorption efficacy.Publication Metadata only Formation of nano CoFe2O4 crystallites in hydroxyapatite(2007-08-23) Weeraphat Pon-On; I. Ming Tang; Mahidol University; The Institute of Science and Technology for Research and Development, Mahidol Universityinto the Ca(1) sites in HAP lattice when the HAP is heated above 750°C. SEM show that crystallites of irregular shapes coalesced into larger aggregates of cubic symmetrical structure characteristic of CoFe2O4 spinel as the annealing temperature is increased.Publication Metadata only Cation distribution and magnetic behavior of Mg1 - XZn xFe2O4 ceramics monitored by Mössbauer Spectroscopy(2006-07-01) S. Ounnunkad; P. Winotai; S. Phanichphant; Chiang Mai University; Mahidol Universitysolid-state reaction using a mixed oxide method. All XRD patterns revealed only the monophasic spinel characteristic structure of MgFe2O4. The lattice parameters increased with the increasing of Zn content. Saturation magnetization (MS) of the ferritesPublication Metadata only Late Triassic back-arc spreading and initial opening of the Neo-Tethyan Ocean in the northern margin of Gondwana: Evidences from Late Triassic BABB-type basalts in the Tethyan Himalaya, Southern Tibet(2020-04-01) Chao Lin; Jinjiang Zhang; Xiaoxian Wang; Prinya Putthapiban; Bo Zhang; Kai Liu; Tianli Huang; Chinese Academy of Sciences; Peking University; Mahidol University; China Earthquake Administrationmelting in the spinel stability field. They underwent slight crustal contamination as well as the fractional crystallization of clinopyroxene. The T3n basalts are similar to typical back-arc basin basalts (BABB) such as the Okinawa BABB. This indicates