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MRI-Based Visualization of the Relaxation Times of Early Somatic Embryos

Abstract

The large set of scientific activities supported by MRI includes, among others, the research of water and mineral compounds transported within a plant, the investigation of cellular processes, and the examination of the growth and development of plants. MRI is a method of major importance for the measurement of early somatic embryos (ESE) during cultivation, and in this respect it offers several significant benefits discussed within this paper. We present the following procedures: non-destructive measurement of the volume and content of water during cultivation; exact three-dimensional differentiation between the ESEs and the medium; investigation of the influence of ions and the change of relaxation times during cultivation; and multiparametric segmentation of MR images to differentiate between embryogenic and non-embryogenic cells. An interesting technique consists in two-parameter imaging of the relaxation times of the callus; this method is characterized by tissue changes during cultivation at a microscopic level, which can be monitored non-destructively.

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Redetermination of Zero-Field Splitting in [Co(qu)2Br2] and [Ni(PPh3)2Cl2] Complexes

Abstract

A mononuclear CoII complex, [Co(qu)2Br2], and NiII complex, [Ni(PPh3)2Cl2], (qu = quinoline, PPh3 = triphenylphosphine) have been reinvestigated. Their crystal and molecular structures are reported along with IR and UV-Vis spectra. Magnetism of both complexes has been studied by using the DC SQUID magnetometry. These complexes exhibit a moderate magnetic anisotropy expressed by zero-field splitting parameter D. The D-value is positive for both complexes with D/hc = +5.94 cm−1 and D/hc = +12.76 cm−1, that is also confirmed by ab initio calculations.

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Magnetic Resonance Imaging of Surgical Implants Made from Weak Magnetic Materials

), 3293-3300. [13] Schenck, J.F. (1996). The role of magnetic susceptibility in magnetic resonance imaging: MRI magnetic compatibility of the first and second kinds. Medical Physics , 23 (6), 815-851. [14] Shellock, F.G. (2002). Biomedical implants and devices: Assessment of magnetic field interactions with a 3.0-Tesla MR system. Journal of Magnetic Resonance Imaging , 16, 721-732.

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The emplacement mode of Upper Cretaceous plutons from the southwestern part of the Sredna Gora Zone (Bulgaria): structural and AMS study

, Bulgaria. Geol. Soc. Amer. Bull. 89, 439-447. Borradaile G.J. 1988: Magnetic susceptibility, petrofabrics and strain. Tectonophysics 156, 1-20. Borradaile G.J. & Henry B. 1997: Tectonic applications of magnetic susceptibility and its anisotropy. Earth. Sci. Rev. 42, 49-93. Bouchez J.-L. 1997: Granite is never isotropic: an introduction to AMS studies of granitic rocks. In: Bouchez J.-L., Hutton D.H.W. & Stephens W.E. (Eds.): Granite: from segregation of melt to emplacement fabrics

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Formation of Fe and Ni substituted LiMn2–XMXO4 nanopowders and their crystal and electronic structure and magnetic properties

line is clearly visible in the spectrum. For these lines, the background individually selected in the region limited to the particular line is subtracted and after that integration of the peak area is performed [ 56 ]. The Gaussian-Lorentzian functions were used to fit the XPS core level spectra. Magnetic susceptibility was measured using the SQUID Magnetometer MPMS-XL-7AC (Quantum Design) in the temperature range of 2 K to 400 K. The 57 Fe Mössbauer spectrum was recorded at room temperature using a constant acceleration spectrometer with 57 Co:Cr source. The

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Luminescence chronostratigraphy for the loess deposits in Złota, Poland

, palaeopedology and stratigraphy allowing to interpret the geological history of this place. The investigations of magnetic susceptibility, grain-size distribution or the organic carbon contents aim at obtaining a reliable stratigraphy of the loess sediment in Poland, which in conjunction with the chronostratigraphy will correspond to similar investigations led in other countries, like the chronostratigraphy created by other researchers in Europe, especially in the Serbia, Czech Republic, Germany and Ukraine ( Fuchs et al ., 2008 ; Fuchs et al ., 2013 ; Antoine et al

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OSL chronostratigraphy for loess deposits from Tyszowce – Poland

material, namely silt-sized quartz fraction (45–63 μm) and polymineral fine grained material (4–11 μm). The profile in Tyszowce was also sampled in a continuous vertical section at close intervals of ca . 5 cm and documented in respect of its sedimentology, palaeopedology and stratigraphy. For all samples grain-size distribution, carbonate and organic carbon contents, geochemical composition and magnetic susceptibility were determined. For the upper part of the profile, 7 samples for radiocarbon dating were also collected and analysed. The stratigraphy of the Tyszowce

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Paleoenvironments during the Rhaetian transgression and the colonization history of marine biota in the Fatric Unit (Western Carpathians)

coeval sequences in the Anti-Atlas, Morocco. Palaeogeogr. Palaeoclimatol. Palaeoecol. 167, 73-100. Cullers R.L. 2000: The geochemistry of shales, siltstones and sandstones of Pennsylvanian-Permian age, Colorado, USA: implications for provenance and metamorphic studies. Lithos 51, 181-203. Da Silva A.-C., Mabille C. & Boulvain F. 2009: Influence of sedimentary setting on the use of magnetic susceptibility: examples from the Devonian of Belgium. Sedimentology 56, 1292-1306. Devleeschouwer X., Petitclerc E., Spassov S

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A strange antiferromagnetic phase has controlled the magnetic and paleomagnetic properties of the Fe-Ti inversion spinel bearing rocks on the whole Earth globe

, 83-102. Orlický O., 1988: The determination of Curie temperatures and magnetic phase state of the Fe and Fe-Ti minerals on the base of the change of their magnetic susceptibility with the temperature. Mineralia Slovaka, 20, 519-536 (in Slovak). Orlický O., Fitykas M., Beˇnka J., Lipka J., Mihalíková A., Toman B., 1988: Magnetic and mineralogical investigation of remanent magnetization carriers in selected andesites and olivine basanites from Greece. Geologica Carpathica, 39, 4, 489-504 Orlický O., 1990: Detection of magnetic carriers

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Magnetic characterization of microcrystalline Na3Ln0.99–xEr0.01Crx(PO4)2 orthophosphates synthesized by Pechini method (Ln = La, Gd)

Abstract

Na3Ln(PO4)2 orthophosphates (Ln = La, Gd) doped with Er3+ and co-doped with Cr3+ ions were synthesized by Pechini method and characterized by electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. Low temperature EPR spectra were detected and analyzed in terms of temperature dependence and the structure of the obtained materials. They show that erbium and chromium ions substitute Ln3+ and also Na+ ions or Na+ channels forming complex EPR spectra. Both kinds of ions reveal ferromagnetic type of interaction which shows some anomaly at the temperature between 10 K and 15 K. Magnetic susceptibility reveals a weak antiferromagnetic kind of interaction dominating in the whole temperature range, from 3.5 to 300 K.

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