The Correlation Analysis of Magnetic Susceptibility and Elemental Composition of Very Fine Sand from Anoi Itam Beach in Weh Island, Aceh

Abstract Ironsand deposits might contain Fe as well as other valuable elements and minerals that could be used in a variety of applications. Often, high Fe content deposits are preferable for exploration. An earlier study shows that the highest Fe content is found in the very fine sand (VFS) size. In this study, seven VFS samples from Anoi Itam were subjected to magnetic measurements as well as X-Ray florescence (XRF), X-Ray diffraction (XRD), and correlation analyses to investigate further characteristics and how magnetic susceptibility correlates with the elemental composition of ironsand. Magnetic susceptibility varies from 2207.77 × 10-8 m3 kg-1 to 4476.68 × 10-8 m3 kg-1. The main elements contained in the sample are Fe, Ti, Si, and Al. Meanwhile, other elements have small concentrations (<2%). Based on XRD analyses, magnetite and ilmenite are the main minerals with varying concentrations in each sample. The correlation analysis shows that magnetic susceptibility has a weak correlation with Fe probably because Fe forms minerals with very different magnetism, namely magnetite and ilmenite.

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Ferromagnetic interactions in a dicyanamide-bridged multinuclear metal-organic framework [Pr3NH]+ [Mn(dca)3]−·H2O

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0015 ◽

2019 ◽

Vol 74 (6) ◽

pp. 485-489

Author(s):

Yuan Huang ◽

Xiu-feng Yu ◽

Zhen Rong ◽

Yi-chun Ai ◽

Kun Qian ◽

...

Keyword(s):

Magnetic Susceptibility ◽

Magnetic Measurements ◽

Metal Organic Framework ◽

Three Dimensional ◽

X Ray Diffraction ◽

Magnetic Susceptibility Data ◽

X Ray ◽

Susceptibility Data ◽

Metal Organic ◽

Ferromagnetic Interactions

AbstractA new complex [Pr3NH]+ [Mn(dca)3]− · H2O (dicyanamide = dca−) was synthesized, in which the Mn2+ cations are bridged by end-to-end dca anions to form three-dimensional [Mn(dca)3]nn− networks and tripropylammonium cations reside in the cavities of these networks. The complex has been characterized by single-crystal X-ray diffraction, infrared spectroscopy, elemental analysis, and magnetic measurements. Magnetic susceptibility data indicate ferromagnetic interactions among the MnII ions.

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Crystal growth and physical properties of an antiferromagnetic molecule: trans-dibromidotetrakis(acetonitrile)chromium(III) tribromide, [CrBr2(NCCH3)4](Br3)

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520621004662 ◽

2021 ◽

Vol 77 (4) ◽

Author(s):

Ranuri S. Dissanayaka Mudiyanselage ◽

Tai Kong ◽

Weiwei Xie

Keyword(s):

Magnetic Susceptibility ◽

Magnetic Measurements ◽

Interaction Analysis ◽

Theoretical Calculations ◽

Magnetic Feature ◽

Maximum Temperature ◽

Neel Temperature ◽

X Ray Diffraction ◽

Néel Temperature ◽

X Ray

The synthesis, crystal structure determination, magnetic properties and bonding interaction analysis of a novel 3d transition-metal complex, [CrBr2(NCCH3)4](Br3), are reported. Single-crystal X-ray diffraction results show that [CrBr2(NCCH3)4](Br3) crystallizes in space group C2/m (No. 12) with a symmetric tribromide anion and the powder X-ray diffraction results show the high purity of the material specimen. X-ray photoelectron studies with a combination of magnetic measurements demonstrate that Cr adopts the 3+ oxidation state. Based on the Curie–Weiss analysis of magnetic susceptibility data, the Néel temperature is found to be around 2.2 K and the effective moment (μeff) of Cr3+ in [CrBr2(NCCH3)4](Br3) is ∼3.8 µB, which agrees with the theoretical value for Cr3+. The direct current magnetic susceptibility of the molecule shows a broad maximum at ∼2.3 K, which is consistent with the theoretical Néel temperature. The maximum temperature, however, shows no clear frequency dependence. Combined with the observed upturn in heat capacity below 2.3 K and the corresponding field dependence, it is speculated that the low-temperature magnetic feature of a broad transition in [CrBr2(NCCH3)4](Br3) could originate from a crossover from high spin to low spin for the split d orbital level low-lying states rather than a short-range ordering solely; this is also supported by the molecular orbital diagram obtained from theoretical calculations.

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Synthesis, structure, photoluminescent, optical and magnetic properties of a novel thulium p-hydroxybenzenesulfonate complex

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1515/zkri-2017-2105 ◽

2019 ◽

Vol 234 (3) ◽

pp. 177-182

Author(s):

Rong-Hua Hu ◽

Wen-Tong Chen ◽

Jian-gen Huang

Keyword(s):

Magnetic Susceptibility ◽

Solid State ◽

Diffuse Reflectance ◽

Magnetic Measurements ◽

Variable Temperature ◽

X Ray Diffraction ◽

Monoclinic System ◽

X Ray ◽

Elemental Analyses ◽

Anti Stokes

Abstract A novel thulium p-hydroxybenzenesulfonate complex [Tm(C6H5O4S)2(H2O)6](C6H5O4S)·3H2O (1) was solvothermally synthesized and characterized by elemental analyses, photoluminescence, solid-state UV/vis diffuse reflectance, magnetic measurements and single-crystal X-ray diffraction. Complex 1 features an ionic structure with the thulium ion possessing a square antiprismatic geometry. Complex 1 crystallized in the monoclinic system with space group P21. Photoluminescent measurements with solid-state sample demonstrate that the anti-Stokes emission bands in the red/NIR spectral region 710 and 812 nm are observed from the Tm3+ 4f intrashell transitions from the 3F2,3 excited states to the 3H6 and 1G4 excited state to the 3H5 state, respectively. Solid-state UV/vis diffuse reflectance spectra of complex 1 show the existence of a wide optical band gap of 3.56 eV. Variable-temperature magnetic susceptibility and field dependence magnetization measurements are also studied and the magnetic susceptibility obeys the Curie-Weiss law (χm=c/(T−θ)) with the value C being of 8.6 K and a negative Weiss constant θ being of −0.2 K.

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Synthesis, crystal structure, and magnetic properties of the complex [(CH3)3NH]2 [Co(NCS)4]

Zeitschrift für Naturforschung B ◽

10.1515/znb-2018-0069 ◽

2018 ◽

Vol 73 (8) ◽

pp. 571-575

Author(s):

Yang Jie ◽

Huang Yuan ◽

Zhong YouQuan ◽

Fang Ting ◽

Hao Fan ◽

...

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Magnetic Susceptibility ◽

Infrared Spectroscopy ◽

Magnetic Measurements ◽

X Ray Diffraction ◽

Magnetic Susceptibility Data ◽

X Ray ◽

Susceptibility Data ◽

Ferromagnetic Interactions

AbstractA new complex [(CH3)3NH]2[Co(NCS)4], in which zero-dimensional [Co(NCS)4]n2− anions are balanced by 2n [(CH3)3NH]+ cations, was synthesized. The complex has been characterized by single X-ray diffraction, infrared spectroscopy, elemental analysis, and magnetic measurements. Magnetic susceptibility data indicate ferromagnetic interactions among the CoII ions.

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INFLUENCE OF THE PREPARATION CONDITIONS AND THERMAL TREATMENT ON THE STRUCTURE OF THE B2O3-BaO-Fe2O3 SYSTEM

International Journal of Modern Physics B ◽

10.1142/s0217979205029535 ◽

2005 ◽

Vol 19 (10) ◽

pp. 1821-1834 ◽

Cited By ~ 3

Author(s):

DORINA RUSU ◽

M. F. CARRASCO ◽

MONICA TODERAS ◽

I. ARDELEAN

Keyword(s):

Magnetic Field ◽

Magnetic Susceptibility ◽

Thermal Treatment ◽

Optical Microscopy ◽

Magnetic Measurements ◽

Iron Ions ◽

X Ray Diffraction ◽

X Ray ◽

Preparation Conditions ◽

Cooling Method

The structure of x Fe 2 O 3·(100-x)[3 B 2 O 3· BaO ] system with 0≤x≤50 mol % was studied by DTA, X-ray diffraction, density, optical microscopy and EPR measurements in vitreous and partial crystallized state, the samples being obtained by under cooling method. The data obtained show that, by melting the samples at Te = 1200°C or Te = 1250° C , glasses for x≤35 mol % were obtained, and the forming of crystalline microprecipitates of Fe 2 O 3 in the sample with x = 50 mol %. It was also established that the thermal treatment at 565°C without and in the presence of magnetic field of 0.7 T is influencing the forming and the development of the Fe 2 O 3 microcrystals in samples with x≥35 mol %. The samples melted at Tc = 1200° C and Tc = 1250° C were studied by magnetic susceptibility measurements which evidenced similar results with those obtained by EPR. Also, the magnetic measurements show that for the thermal untreated samples the iron ions participate at superexchange interactions for x≥5 mol % and for x≥10 mol %, respectively.

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Structural and Magnetic Characterizations of Ruddlesden–Popper Family (Ca2-xNdxMnO4) Compound Synthesized by Ceramic Route

Journal of Low Temperature Physics ◽

10.1007/s10909-021-02566-y ◽

2021 ◽

Author(s):

H. Issaoui ◽

F. Issaoui ◽

E. Dhahri ◽

E. K. Hlil

Keyword(s):

Magnetic Susceptibility ◽

Magnetic Measurements ◽

Orthorhombic Phase ◽

X Ray Diffraction ◽

Temperature Dependent ◽

Solid State Method ◽

X Ray ◽

Dramatic Difference ◽

Ceramic Route ◽

Moriya Interaction

AbstractIn this work, we were interested in the Ca2−xNdxMnO4 compounds when (0.1 ≤ x ≤ 0.4). These oxides are synthesized through the solid-state method. In this study, we investigated the evolution of the structure, the magnetic properties and the Mn3+/Mn4+ ratio with the Nd content. The morphological study shows a decrease in the size of the grain in relation to x. The X-ray diffraction reveals a transition from the tetragonal phase to the orthorhombic phase when x = 0.4. Magnetic measurements have been taken for all the compounds in the temperature range between 2 and 300 K. The temperature-dependent magnetic susceptibility shows the presence of three transitions TN, TC and TCO. A dramatic difference in magnetic susceptibility between ZFC and FC was observed below the Neel temperatures for Ca2-xNdxMnO4, which shows the onset of a ferromagnetic moment below these temperatures. This moment is caused by the Dzyaloshinskii–Moriya interaction.

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Ternary Antimonides RE4T7Sb6 (RE=Gd–Lu; T =Ru, Rh) with Cubic U4Re7Si6-type Structure

Zeitschrift für Naturforschung B ◽

10.5560/znb.2013-3181 ◽

2013 ◽

Vol 68 (9) ◽

pp. 971-978 ◽

Cited By ~ 2

Author(s):

Inga Schellenberg ◽

Ute Ch. Rodewald ◽

Christian Schwickert ◽

Matthias Eul ◽

Rainer Pöttgen

Keyword(s):

Magnetic Susceptibility ◽

Single Crystal ◽

Magnetic Moment ◽

Induction Furnace ◽

X Ray Diffraction ◽

Temperature Dependent ◽

X Ray ◽

Antiferromagnetic Ordering ◽

Arc Melting ◽

Intermediate Valent

The ternary antimonides RE4T7Sb6 (RE=Gd-Lu; T =Ru, Rh) have been synthesized from the elements by arc-melting and subsequent annealing in an induction furnace. The samples have been characterized by powder X-ray diffraction. Four structures were refined on the basis of single-crystal X-ray diffractometer data: U4Re7Si6 type, space group Im3m with a=862.9(2) pm, wR2=0.0296, 163 F2 values for Er4Ru7Sb6; a=864.1(1) pm, wR2=0.1423, 153 F2 values for Yb4Ru7Sb6; a=872.0(2) pm, wR2=0.0427, 172 F2 values for Tb4Rh7Sb6; and a=868.0(2) pm, wR2=0.0529, 154 F2 values for Er4Rh7Sb6, with 10 variables per refinement. The structures have T1@Sb6 octahedra and slightly distorted RE@T26Sb6 cuboctahedra as building units. The distorted cuboctahedra are condensed via all trapezoidal faces, and this network leaves octahedral voids for the T1 atoms. The ruthenium-based series of compounds was studied by temperature-dependent magnetic susceptibility measurements. Lu4Ru7Sb6 is Pauli-paramagnetic. The antimonides RE4Ru7Sb6 with RE=Dy, Ho, Er, and Tm show Curie-Weiss paramagnetism. Antiferromagnetic ordering occurs at 10.0(5), 5.1(5) and 4.0(5) K for Dy4Ru7Sb6, Ho4Ru7Sb6 and Er4Ru7Sb6, respectively, while Tm4Ru7Sb6 remains paramagnetic. Yb4Ru7Sb6 is an intermediate-valent compound with a reduced magnetic moment of 3.71(1) μB per Yb as compared to 4.54 μB for a free Yb3+ ion

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Dissimilatory Iron-Reducing Microorganisms Are Present and Active in the Sediments of the Doce River and Tributaries Impacted by Iron Mine Tailings from the Collapsed Fundão Dam (Mariana, MG, Brazil)

Minerals ◽

10.3390/min11030244 ◽

2021 ◽

Vol 11 (3) ◽

pp. 244

Author(s):

Carolina N. Keim ◽

Jilder D. P. Serna ◽

Daniel Acosta-Avalos ◽

Reiner Neumann ◽

Alex S. Silva ◽

...

Keyword(s):

Bottom Sediments ◽

Magnetic Measurements ◽

Culture Media ◽

X Ray Diffraction ◽

X Ray ◽

Ferric Oxyhydroxide ◽

Transmission Electron ◽

Iron Mine ◽

Organic Matter Oxidation ◽

Doce River

On 5 November 2015, a large tailing deposit failed in Brazil, releasing an estimated 32.6 to 62 million m3 of iron mining tailings into the environment. Tailings from the Fundão Dam flowed down through the Gualaxo do Norte and Carmo riverbeds and floodplains and reached the Doce River. Since then, bottom sediments have become enriched in Fe(III) oxyhydroxides. Dissimilatory iron-reducing microorganisms (DIRMs) are anaerobes able to couple organic matter oxidation to Fe(III) reduction, producing CO2 and Fe(II), which can precipitate as magnetite (FeO·Fe2O3) and other Fe(II) minerals. In this work, we investigated the presence of DIRMs in affected and non-affected bottom sediments of the Gualaxo do Norte and Doce Rivers. The increase in Fe(II) concentrations in culture media over time indicated the presence of Fe(III)-reducing microorganisms in all sediments tested, which could reduce Fe(III) from both tailings and amorphous ferric oxyhydroxide. Half of our enrichment cultures converted amorphous Fe(III) oxyhydroxide into magnetite, which was characterized by X-ray diffraction, transmission electron microscopy, and magnetic measurements. The conversion of solid Fe(III) phases to soluble Fe(II) and/or magnetite is characteristic of DIRM cultures. The presence of DIRMs in the sediments of the Doce River and tributaries points to the possibility of reductive dissolution of goethite (α-FeOOH) and/or hematite (α-Fe2O3) from sediments, along with the consumption of organics, release of trace elements, and impairment of water quality.

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