scholarly journals Magnetic Susceptibility of Soils from Eastern Botswana: A Reconnaissance Survey and Potential Applications

2015 ◽  
Vol 7 (4) ◽  
pp. 45 ◽  
Author(s):  
Rubeni Tawanda Ranganai ◽  
Moikwathai Moidaki ◽  
James G. King
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Land Use Planning ◽  
Magnetic Measurements ◽  
Parent Material ◽  
Appreciable Amount ◽  
Frequency Dependent ◽  
Magnetic Susceptibilities ◽  
Basement Rocks ◽  
Rock And Soil

<p class="zhengwen">Soil magnetic properties measurements are relatively fast and inexpensive but have been proved to be sufficient for preliminary investigations in diverse socio-developmental issues. This paper presents results of a reconnaissance study of soil colour and magnetic susceptibility (c) in eastern Botswana, where ~80% of the population resides. The work is a first step to creating a database of rock and soil magnetic properties and to document spatial variations in magnetic properties in the country. These measurements are important as constraints for interpretation of available aeromagnetic data and can also be exploited for environmental soil research (pollution) and land-use planning (agriculture). The soils sampled include derivatives of varying types and provenance such as Archean gneissic granitoids, metamorphosed rocks (granulites), volcano-sedimentary assemblages, Karoo basalts, and alluvial sediments. A soil colour chart was used since soil colours and magnetic properties are diagnostic of its parent rock sources and weathering profiles. Soil magnetic susceptibilities were measured at both low frequency (0.46 MHz, clf) and high frequency (4.6 MHz, chf), thus allowing calculation of frequency-dependent susceptibility (cfd, cfd%) for detecting ultra-fine ferromagnetic minerals.</p>It was found that soils with Hues ranging from 7.5YR to 10YR have appreciable amount of magnetic materials and soils with Hues of 2.5YR are generally nonmagnetic. The results of soil magnetic susceptibility profiles show spatial variation closely related to the variation in basement rocks, which provides excellent evidence that the magnetic susceptibility variation reflects basement rocks or bedrock composition (soil parent material). In relation to the Botswana physiographic units, soils from the hardveld (Precambrian) show the highest susceptibilities, followed by those from the sandveld, with the lowest values being from the alluvial. The frequency dependent magnetic susceptibilities indicate the presence of ultra-fine super-paramagnetic minerals such as magnetite/maghemite. It is suggested that a systematic and continuous programme of rock and soil magnetic measurements would benefit various socio-economic and development priority sectors of Botswana. This also applies to many developing countries in Africa where soil physics and measurement of soil susceptibility in particular, is generally still at an embryonic stage.

High Temperature and High Pressure Synthesis and Magnetic Properties of Arsenic-Based Filled Skutterudite Compounds

2019 ◽  
Vol 289 ◽  
pp. 85-92
Author(s):  
Chihiro Sekine ◽  
Toshihide Osanai ◽  
Hariharan Ponmani ◽  
Atachariya Phuangyod ◽  
Yukihiro Kawamura ◽  
...  
Keyword(s):  
High Pressure ◽  
Magnetic Properties ◽  
Electrical Resistivity ◽  
Magnetic Susceptibility ◽  
Magnetic Measurements ◽  
Spin Fluctuations ◽  
Filled Skutterudite ◽  
Lattice Constants ◽  
Pressure Synthesis ◽  
New Superconductor

We have succeeded in synthesizing new arsenic-based filled skutterudite compounds CaFe4As12and BaOs4As12under high pressure. These compounds have lattice constants of 8.3288 and 8.5809 Å, respectively. The magnetic properties of CaFe4As12and BaOs4As12have been studied by means of electrical resistivity, magnetic susceptibility and magnetization measurements. The electrical resistivity and magnetic measurements indicate that CaFe4As12is a nearly ferromagnetic metal with spin fluctuations of Fe 3delectrons and BaOs4As12is a new superconductor with a transition temperature around 3 K.

Magnetic properties and structure of some copper(II) complexes of pyridine and quinoline N-oxides

1967 ◽  
Vol 20 (11) ◽  
pp. 2403 ◽  
Author(s):  
SJ Gruber ◽  
CM Harris ◽  
E Kokot ◽  
SL Lenzer ◽  
TN Lockyer ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Magnetic Moments ◽  
Paramagnetic Complex ◽  
Water Molecules ◽  
Acetate Monohydrate ◽  
Binuclear Copper ◽  
Kcal Mole ◽  
Ferromagnetic Interaction ◽  
Magnetic Susceptibilities

The magnetism of various copper(II) complexes of pyridine and quinoline N-oxides1 has been further investigated. The compounds Cu(C5H5NO)nX2 (where n = 4 or 6, X = ClO4; n = 2, X = Cl, Br, NCS; n = 1, X = Cl, Br, CH3COO) and Cu(C9H7NO)nX2 where n = 4, X = ClO4; n = 2, X = Cl, Br, NO3; n = 1, X = Cl, Br, CH3COO) have been studied. The variation of the magnetic susceptibilities of most of these compounds is reported over a temperature range. The variation of the magnetic susceptibility with temperature for the weakly paramagnetic complex Cu(C5H5NO)Cl2 is discussed in terms of the binuclear oxygen-bridged structure previously postulated.1 The compound exhibits anti-ferromagnetic interaction between pairs of copper(II) atoms with a singlet-triplet separation of 2.1 kcal/mole. The compounds Cu(C5H5NO)2Cl2, Cu(C5H5NO)Br2, and Cu(C9H7NO)X2 (X = Cl, Br) are more weakly paramagnetic due to a larger singlet-triplet separation. The compound Cu(C5H5NO)2Br2 possesses a higher paramagnetic susceptibility than those of the previous compounds, and its magnetic properties are consistent with a dimeric structure involving a singlet- triplet separation of 0.7 kcal/mole. The copper(II) acetate adducts, Cu(CH3COO)2,L (L = C5H5NO or C9H7NO), possess very similar magnetic properties to binuclear copper(II) acetate monohydrate and presumably possess a similar structure, with the N-oxides replacing the water molecules. These compounds exhibit singlet-triplet energies of c. 1 kcal/mole similar to values reported for a large number of copper(II) alkanoates. The compounds Cu(C5H5NO)2(NCS)2, Cu(C5H5NO)4(ClO4)2, Cu(C5H5NO)6- (ClO4)2, Cu(C9H7NO)2X2 (X = Cl, Br, NO3), all obey the Curie-Weiss law and possess mean magnetic moments of 1.89, 1.80, 1.93, 1.88, 1.96, and 1.88 B.M. (corrected for θ values of -12, -7, -8, + -4, and -16�) respectively.

The magnetic properties of natural pigments: preliminary analyses for their identification in Fine Arts

2021 ◽  
Author(s):  
Chiara Anselmi ◽  
Antonio Sgamellotti ◽  
Manuela Vagnini ◽  
Aldo Winkler
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Magnetic Measurements ◽  
Rock Magnetism ◽  
Fine Arts ◽  
Magnetic Behavior ◽  
Spectroscopic Techniques ◽  
Magnetic Carriers ◽  
Magnetic Techniques ◽  
Synthetic Pigments

&lt;p&gt;A multidisciplinary approach, including compositional, spectroscopic and microscopic methodologies, is often used for the analysis and identification of pigments in Fine Arts. Although a large part of widely used natural and synthetic pigments contain Fe-oxides and hydroxides, their magnetic characterization is still poorly explored. The application of rock magnetism analyses through fast, cheap and non-destructive measurements, can be instead useful for the identification and discrimination of pigments through their distinctive magnetic properties.&lt;/p&gt;&lt;p&gt;In this preliminary study, the magnetic properties of several iron-based commercial pigments together with paintings models and supports, were analyzed.&lt;/p&gt;&lt;p&gt;In order to investigate the compositional differences of pigments by means of their magnetic behavior, the magnetic susceptibility, the hysteresis properties and the magnetic susceptibility variation at low and high temperature were measured on selected samples.&lt;/p&gt;&lt;p&gt;All the pigments showed different magnetic properties, mainly related to variable proportions of magnetite, hematite and maghemite as the main magnetic carriers.&lt;/p&gt;&lt;p&gt;Further studies will be addressed to define a protocol for applying the magnetic techniques to the characterization of pigments, including tests on samples produced by different brands and different periods, with the final aim of integrating the magnetic measurements with the different spectroscopic techniques commonly employed for the preservation and the analysis of cultural heritage.&lt;/p&gt;

Magnetic Susceptibility and Structure of Some Transition Metal (II) Complexes with 1,2,4-Triazole

1977 ◽  
Vol 32 (7) ◽  
pp. 783-784 ◽  
Author(s):  
D. W. Engelfriet ◽  
J. G. Haasnoot ◽  
W. L. Groeneveld
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Transition Metal ◽  
Metal Ions ◽  
Single Crystal ◽  
Two Dimensional ◽  
Single Crystal Diffraction ◽  
Magnetic Susceptibilities ◽  
X Ray

Abstract The magnetic susceptibilities of some transition metal (II) complexes with 1,2,4-triazole (trz) have been measured in the range 2-300 K. Ni (trz)2 (NO3)2 (H2O) 8/3, Ni (trz)2 SO4 (H2O)5 and α-Ni (trz)2 (NCS)2 are found to be linear antiferromagnetic trimers. For β- Ni (trz)2 (NCS)2 and similar compounds with Mn (II), Fe (II), Co (II) and Cu(II), totally different magnetic properties were observed, suggesting the presence of two-dimensional networks of metal ions bridged by 1,2,4-triazole molecules. For Co (trz) 2 (NCS) 2 this was confirmed by X-ray single crystal diffraction.

The Magnetic Susceptibility of Southwestern Obsidian: An Exploratory Study

1997 ◽  
Vol 17 (4) ◽  
pp. 271-285 ◽  
Author(s):  
Tim Church ◽  
Carlos Caraveo
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Exploratory Study ◽  
Magnetic Measurements ◽  
Eastern Mediterranean ◽  
Volcanic Glass

The magnetic properties of volcanic glass and obsidian have long been known. Selected magnetic properties have proven useful discriminators among eastern Mediterranean obsidian sources. A recent exploratory study of the magnetic susceptibility of Southwestern obsidians indicates that it may prove a useful tool in this region also. Magnetic measurements of samples from many of the major obsidian sources in the Southwest were analyzed in an exploratory study of the technique and the resulting data are presented here. The technique and its limitations are also discussed.

scholarly journals Spectral, thermal and magnetic properties of Cu(II) and Ni(II) complexes with Schiff base ligands

2011 ◽  
Vol 76 (12) ◽  
pp. 1639-1648 ◽  
Author(s):  
Beata Cristóvão
Keyword(s):  
Thermal Analysis ◽  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Ir Spectroscopy ◽  
Magnetic Measurements ◽  
Magnetic Moments ◽  
Schiff Base Ligands

Mononuclear copper(II) and nickel(II) complexes of the formulae [Cu(L1)] (1), [Ni(L1)] (2), [Cu(L2)] (3) and [Cu(L3)H2O] (4) (where L1 = N,N?-ethylenebis(4,6-dimethoxysalicylidenaminato), L2 = N,N?-ethylenebis(5-bromosalicylidenaminato) and L3 = N,N?-ethylenebis(5-bromo-3-methoxysalicylidenaminato)) were synthesized as microcrystalline powders and characterized by IR spectroscopy, thermal analysis and magnetic measurements. The magnetic susceptibility of the Cu(II) complexes changed with temperature according to the Curie-Weiss law. The complexes 1, 3 and 4 exhibit magnetic moments of 2.29, 2.20 and 1.88 ?B, respectively, at 303 K. These values practically do not change with lowering the temperature to 77 K. The nickel(II) complex 2 is diamagnetic.

THE MAGNETIC SUSCEPTIBILITIES OF SOME DIAMAGNETIC ALLOYS: THE PRIMARY SOLID SOLUTIONS OF CADMIUM, INDIUM, TIN, AND ANTIMONY IN COPPER AND IN SILVER; ZINC, GALLIUM, GERMANIUM, AND ARSENIC IN SILVER; COPPER IN SILVER AND SILVER IN COPPER

1960 ◽  
Vol 38 (7) ◽  
pp. 908-926 ◽  
Author(s):  
W. G. Henry ◽  
J. L. Rogers
Keyword(s):  
Magnetic Properties ◽  
Density Of States ◽  
Solid Solutions ◽  
Magnetic Measurements ◽  
Free Electrons ◽  
Atom Ratio ◽  
Magnetic Susceptibilities ◽  
Silver Copper ◽  
Copper Zinc ◽  
Cadmium Indium

The results of the measurements of the variation with concentration of the magnetic susceptibility in the solid solutions of the following systems are presented: copper with silver, cadmium, indium, tin, and antimony as solutes; silver with copper, zinc, gallium, germanium, arsenic, cadmium, indium, tin, and antimony as solutes. The density of states for silver is calculated by using the approximation to nearly free electrons. It is found that the density of states is decreasing at an electron to atom ratio of 1.0. It is further found that the method used in an earlier paper to discuss the magnetic properties of the α-solid solutions formed with copper by zinc, gallium, germanium, and arsenic is applicable to the monovalent–polyvalent systems of the present paper. It is concluded from the magnetic measurements that the Fermi surface touches the (III) Brillouin zone face in both silver and copper and that the rate of decrease of the density of states with electron to atom ratio is given approximately by the approximation to nearly free electrons. The solid solutions in the silver–copper system are anomalous.

Magnetic characterisation of magnetite and hematite from the Blötberget apatite – iron oxide deposits (Bergslagen), south-central Sweden

2019 ◽  
Vol 56 (9) ◽  
pp. 948-957 ◽  
Author(s):  
Bjarne S.G. Almqvist ◽  
Andreas Björk ◽  
Hannes B. Mattsson ◽  
Daniel Hedlund ◽  
Klas Gunnarsson ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Iron Oxide ◽  
Inductively Coupled Plasma ◽  
Magnetic Measurements ◽  
Core Material ◽  
Morin Transition ◽  
Oxide Systems ◽  
Weight Percentage ◽  
South Central

Rock magnetic measurements were carried out on drill core material and hand specimens from the Blötberget apatite – iron oxide deposit in the Bergslagen ore province, south-central Sweden, to characterise their magnetic properties. Measurements included several kinds of magnetic susceptibility and hysteresis parameters. Petrographic and scanning electron microscopy were used to independently identify and quantify the amount and type of magnetite and hematite. Two hematite-rich samples were studied with laser ablation inductively coupled plasma mass spectrometry to quantify the trace element chemistry in hematite and investigate the potential influence of trace elements on magnetic properties. Three aspects of this study are noteworthy. (1) Hematite-rich samples display strong anisotropy of magnetic susceptibility, which is likely to affect the appearance and modelling of magnetic anomalies. (2) The magnitude-drop in susceptibility across Curie and Néel temperature transitions shows significant correlation with the respective weight percentage of magnetite and hematite. Temperature-dependent magnetic susceptibility measurements can therefore be used to infer the amounts of both magnetite and hematite. (3) Observations of a strongly depressed Morin transition at approximately −60 to −70 °C (200 to 210 K) are made during low-temperature susceptibility measurements. This anomalous Morin transition is most likely related to trace amounts of V and Ti that substitute for Fe in the hematite. When taken together, these magnetic observations improve the understanding of the magnetic anomaly signature of the Blötberget apatite – iron oxide deposits and may potentially be utilised in a broader context when assessing similar (Paleoproterozoic) apatite – iron oxide systems.

scholarly journals Magnetic susceptibility and related properties of rare-earth crystals

1939 ◽  
Vol 170 (940) ◽  
pp. 112-129 ◽  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Rare Earth ◽  
Specific Heat ◽  
Absorption Spectra ◽  
Room Temperature ◽  
Magnetic Susceptibilities ◽  
Temperature Range ◽  
The Mean

This paper has arisen from attempts to correlate the results of experiments on magnetic susceptibilities, specific heat and absorption spectra of rareearth crystals. No theory has yet been advanced which is capable of giving simultaneous quantitative numerical agreement on all these properties, nor indeed does it seem possible to develop such a theory. For reasons which we shall explain, it seems more likely that some of the data are wrong, or at least, that they have been wrongly interpreted. Many measurements have been made of the magnetic properties of hydrated rare-earth crystals. Accurate values of the mean molecular susceptibility, X , have been obtained over a temperature range from a few degrees absolute to room temperature, and the anisotropy of the susceptibility at room temperature has also been measured

Synthesis, crystal structure, and magnetic properties of an azido-bridged Mn(II) complex [C3H5NH3][Mn(N3)3]

2017 ◽  
Vol 72 (6) ◽  
pp. 409-413 ◽  
Author(s):  
Kun Qian ◽  
Yiyong Xu ◽  
Zengtao Wang ◽  
Jie Yang
Keyword(s):  
Crystal Structure ◽  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Magnetic Measurements ◽  
Antiferromagnetic Interaction ◽  
Magnetic Susceptibility Data ◽  
Susceptibility Data ◽  
Compound C ◽  
Elemental Analyses ◽  
3D Architecture

AbstractA new compound [C3H5NH3][Mn(N3)3] has been synthesized, in which the Mn2+ ions are connected by the end-to-end azide anions to form the 3D architecture, while the C3H5NH3+ cations reside in the cavities of the Mn2+–N3− network, forming rich N−H···N hydrogen bonds with the terminal N atoms of the azide anions. The complex has been characterized by IR spectroscopy, elemental analyses, and magnetic measurements. Magnetic susceptibility data indicate antiferromagnetic interaction among the MnII ions.

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