76 research outputs found
Magnetic fabric in ilmeniterich norites of the Bjerkreimer-Sokndal Layered Intrusion, Norway
The Bjerkreim-Sokndal (BKS) is a layered
intrusion, located in the Mid-
Proterozoic Egersund anorthosite-norite
province within the Sveconorwegian
province of the Baltic Shield, south
Norway. The layered intrusion formed by influxes of more primitive magma
into more evolved magma to produce
six Megacyclic units (MCU), each of
which can be divided into up to six
subunits. From bottom to top in
each megacycle the rocks consist of
early plagioclase-rich norites, intermediate
hemo-ilmenite-rich norites and later
magnetite-rich norites. Aeromagnetic
maps over the intrusion show large
negative and positive anomalies. A
negative anomaly with amplitude to -
13000 nT at 60m above ground is associated
with hemo-ilmenite-rich norite
layer MCU Ive. This layer IVe contains
plagioclase, orthopyroxene, hemoilmenite,
magnetite, and minor clinopyroxene,
biotite, apatite and sulfides.
Multi-domain (MD) magnetite makes
up 2–3% of the rock.
The negative magnetic anomaly associated
with MCU IVe reaches its most
negative value on the east limb of the
Bjerkreim Lobe near Heskestad. The
anomaly at Heskestad is part of a longer
negative anomaly, which follows MCU
IVe for more than 20 km around a large
syncline. The average NRM intensity
decreases from 25AM−1 along the east
fold limb to 10AM−1 towards the hinge
area to 7AM−1 at the hinge. The
BKS has a penetrative deformation fabric
within the syncline with the weakest
deformation found in the hinge area
and the strongest on the east limb. Electron
backscatter diffraction (EBSD) was
used to determine the lattice-preferred
orientation (LPO) of orthopyroxene and
ilmenite. The (100)-planes of the orthopyroxenes
are found to lie parallel
to a foliation in the rock, which is subparallel
to the cumulate layering. Orthopyroxene
c-axes form the steep lineation
within the foliation plane.
The anisotropy of magnetic susceptibility
(AMS) was measured for samples
that were taken at five locations from
the eastern limb to the hinge area of the
syncline to investigate if the change in
NRM intensity could be related to magnetic
fabric.conferenc
Crystallographic—magnetic correlations in single-crystal haemo-ilmenite: new evidence for lamellar magnetism
17 single crystals were identified by electron backscatter diffraction (EBSD) and isolated from coarse massive haemo-ilmenite ore from South Rogaland, Norway. These were studied using the EBSD results, natural remanent magnetization (NRM), and anisotropy of magnetic susceptibility (AMS), to gain a better understanding of angular relationships between crystallographic axes and magnetic properties of haemo-ilmenite in relation to lamellar magnetism. Electron microprobe analyses gave the following average end-member compositions for ilmenite host: 21.1 per cent MgTiO3, 73.7 FeTiO3, 0.5 MnTiO3, 4.3 Fe2O3, 0.2 Cr2O3 and 0.3 V2O3; and for the coarsest (∼3 μm) haematite exsolution lamellae: 3.5 MgTiO3, 22.4 FeTiO3, 71.4 Fe2O3, 1.6 Cr2O3, 1.0 V2O3 and 0.1 Al2O3, making this sample the most Mg- and Cr-rich haemo-ilmenite studied in the province, but with similar element fractionations between the coexisting phases. TEM work on similar material suggests the presence of much thinner exsolution down to 1-2 nm. The EBSD, NRM and AMS results from 12 out of 17 crystals indicate a good agreement between the orientation of crystallographic axes, NRM direction and principal axes of the magnetic susceptibility ellipsoid, with the NRM located in the (0001) basal plane [NRM ∧ (0001) < 6.5°] and the crystallographic c axis quasi-parallel to the minimum axis of the susceptibility ellipsoid [c∧ k3 < 13.5°]. In addition, in 10 of these 12 crystals, the remanent magnetization vector is parallel or nearly parallel to the positive direction of a crystallographic a axis [NRM ∧a < 20°], hence parallel to a principal magnetic moment direction in haematite as determined by Besser, and not parallel to the spin-canted direction of end-member haematite. This is consistent with a basic property of lamellar magnetism, where the magnetic moment is parallel to the principal moments (sublattice magnetization directions) in haematite. Relationships in three additional crystals with NRM ∧a= 22°-33°, only two with good agreement, can be interpreted as consistent with having a magnetic vector quasi-parallel to the spin-canted direction of haematit
Agriculture in the Face of Changing Markets, Institutions and Policies: Challenges and Strategies
Since the late 1980s, agriculture in Central and Eastern European Countries (CEECs) has been under considerable adjustment pressure due to changing political, economic and institutional environments. These changes have been linked to the transition process, as well as the ongoing integration into the European Union and the world market. Reduced subsidies, increased environmental and food quality demands, as well as structural changes in the supply, processing and food retailing sector call for major structural adjustments and the improvement of farmersâ managerial abilities. Though such changes always carry significant threats to farms, they also offer new opportunities for the farms' entrepreneurial engagement. Upcoming changes in the agricultural environment and their possible consequences for farm structures across Europe are thus still timely subjects. The objective of the IAMO Forum 2006 is to contribute to the success of agriculture in the CEECs, as well as their neighboring countries, in todayâs increasingly competitive environment. Concrete questions the conference focuses on are: What are the most suitable farm organizations, cooperative arrangements and contractual forms? How to improve efficiency and productivity? Where do market niches lie and what are the new product demands? This book contains 33 invited and selected contributions. These papers will be presented at the IAMO Forum 2006 in order to offer a platform for scientists, practitioners and policy-makers to discuss challenges and potential strategies at the farm, value chain, rural society and policy levels in order to cope with the upcoming challenges. IAMO Forum 2006, as well as this book, would not have been possible without the engagement of many people and institutions. We thank the authors of the submitted abstracts and papers, as well as the referees, for their evaluation of the abstracts from which the papers were selected. In particular, we would like to express our thanks to OLIVER JUNGKLAUS, GABRIELE MEWES, KLAUS REINSBERG and ANGELA SCHOLZ, who significantly contributed to the organization of the Forum. Furthermore, our thanks goes to SILKE SCHARF for her work on the layout and editing support of this book, and to JIM CURTISS, JAMIE BULLOCH, and DÃNALL Ã MEARÃIN for their English proof-reading. As experience from previous years documents, the course of the IAMO Forum continues to profit from the support and engagement of the IAMO administration, which we gratefully acknowledge. Last but not least, we are very grateful to the Robert Bosch Foundation, the Federal Ministry of Nutrition, Agriculture and Consumer Protection (BMELV), the German Research Foundation (DFG), the Haniel Foundation and the Leibniz Institute of Agricultural Development in Central and Eastern Europe (IAMO) for their respective financial support.Agribusiness, Community/Rural/Urban Development, Farm Management, Industrial Organization, International Development, Labor and Human Capital, Land Economics/Use, Productivity Analysis,
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Adapting agricultural water use to climate change in a post-Soviet context: challenges and opportunities in southeast Kazakhstan
The convergence of climate change and post-Soviet
socio-economic and institutional transformations has been
underexplored so far, as have the consequences of such convergence on crop agriculture in Central Asia. This paper provides a place-based analysis of constraints and opportunities for adaptation to climate change, with a specific focus on water use, in two districts in southeast Kazakhstan. Data were collected by 2 multi-stakeholder participatory workshops, 21 semi-structured in-depth interviews, and secondary statistical data. The present-day agricultural system is characterised by
enduring Soviet-era management structures, but without state inputs that previously sustained agricultural productivity. Low margins of profitability on many privatised farms mean that attempts to implement integrated water management have produced water users associations unable to maintain and upgrade a deteriorating irrigation infrastructure. Although actors
engage in tactical adaptation measures, necessary structural adaptation of the irrigation system remains difficult without significant public or private investments. Market-based water management models have been translated ambiguously to this region, which fails to encourage efficient water use and hinders adaptation to water stress. In addition, a mutual interdependence of informal networks and formal institutions characterises both state governance and everyday life in Kazakhstan. Such interdependence simultaneously facilitates
operational and tactical adaptation, but hinders structural adaptation, as informal networks exist as a parallel system that achieves substantive outcomes while perpetuating the inertia and incapacity of the state bureaucracy. This article has relevance for critical understanding of integrated water management in practice and adaptation to climate change in post-Soviet institutional settings more broadly
Diffraction techniques and vibrational spectroscopy opportunities to characterise bones
From a histological point of view, bones that allow body mobility and protection of internal organs consist not only of different organic and inorganic tissues but include vascular and nervous elements as well. Moreover, due to its ability to host different ions and cations, its mineral part represents an important reservoir, playing a key role in the metabolic activity of the organism. From a structural point of view, bones can be considered as a composite material displaying a hierarchical structure at different scales. At the nanometre scale, an organic part, i.e. collagen fibrils and an inorganic part, i.e. calcium phosphate nanocrystals are intimately mixed to assure particular mechanical properties
Tests of light-lepton universality in angular asymmetries of decays
We present the first comprehensive tests of light-lepton universality in the
angular distributions of semileptonic \Bz-meson decays to charged spin-1
charmed mesons. We measure five angular-asymmetry observables as functions of
the decay recoil that are sensitive to lepton-universality-violating
contributions. We use events where one neutral \B is fully reconstructed in
\PUpsilonFourS{} \to\B\overline{B} decays in data corresponding to \lumion
integrated luminosity from electron-positron collisions collected with the
\belletwo detector. We find no significant deviation from the standard model
expectations
First measurement of as an inclusive test of the anomaly
We measure the tau-to-light-lepton ratio of inclusive -meson branching
fractions , where indicates an electron or muon, and thereby test
the universality of charged-current weak interactions. We select events that
have one fully reconstructed meson and a charged lepton candidate from
of electron-positron collision data collected with the
Belle II detector. We find , in agreement with standard-model expectations. This
is the first direct measurement of
Measurement of branching fractions and direct asymmetries for and decays at Belle II
We report measurements of the branching fractions and direct
asymmetries of the decays , , , and , and use these for testing the standard
model through an isospin-based sum rule. In addition, we measure the branching
fraction and direct asymmetry of the decay and
the branching fraction of the decay . The data are
collected with the Belle II detector from collisions at the
resonance produced by the SuperKEKB asymmetric-energy collider
and contain bottom-antibottom meson pairs. Signal yields are
determined in two-dimensional fits to background-discriminating variables, and
range from 500 to 3900 decays, depending on the channel. We obtain for the sum rule, in agreement with the standard model
expectation of zero and with a precision comparable to the best existing
determinations
Quantification of Thin Film Crystallographic Orientation Using X-ray Diffraction with an Area Detector
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