Oxidized and reduced kaolin fan deposits: Their sedimentological-mineralogical facies and physical-chemical regime (North-Bavarian Kaolin Mining District, Germany)

The kaolin-fan deposits under consideration are sedimentary in origin and they bridge the gap between residual kaolin deposits proximal to the fan apex in crystalline basement rocks and syn(dia)genetic sandstone-hosted kaolin deposits on the fan apron. The “kaolin ore beds” on the other hand, developed in an arenaceous braided-river drainage system (bed load >>> suspended load deposits), reworking into secondary kaolin deposits that took place either intraformationally during the evolution of the kaolin fan deposits or epigenetically after unroofing of the kaolin deposits in high-sinuosity drainage systems passing, locally, into ephemeral lakes and mud flats (suspended load > bed load deposits). The reference type for kaolin fan deposits has been studied in terrigeneous sediments which are largely mined at Hirschau–Schnaittenbach, along the Western edge of the Bohemian Massif, SE Germany. The fan deposits formed under alternating wet and dry subtropical climatic conditions during the early Triassic. Different intensities of uplift in the hinterland and the frequency of tectonic quiescence to tectonic pulse had a strong impact on the paleogradient, facies and hydrography of the kaolin fan deposits, resulting in the build-up of oxidized kaolin fans (OKF) and reduced kaolin fans (RKF). The OKF provide favorable conditions for the accumulation and preservation of kaolin deposits of economic potential, due to a low paleogradient and a continuous rate of uplift. The opposite is the case in the RKF that formed more proximal to the initial residual kaolin deposits and, more basinward, grade into sandstone-hosted (non)-sulfidic faciesbound Pb deposits that were targeted upon during exploration campaigns in the study area. The mineral association of the kaolin fan deposits has been categorized as follows: the allochthonous heavy minerals are zircon, tourmaline, apatite, monazite, xenotime, rutile, garnet, titaniferous magnetite, and ilmenite. They do not significantly vary between OKF and RKF. The autochthonous heavy minerals show strong contrasts in their heavy mineral suites. The RKF are enriched in sulfides and arsenides, which can be deleterious for the kaolin raw material and exclude its use for special final products (anatase, hematite, galena, sphalerite, marcasite, pyrite, bravoite (Ni pyrite), “limonite”, goethite, Ag–Cu–Ni–As sulfides, and barite). The OKF are rather poor in accessory minerals and contain anatase, hematite, and APS minerals. The latter are geo-acidometers (marker minerals for low pH) and considered as an ore guide to high-potential target areas for kaolin. The allochthonous light minerals quartz and K feldspar are common to both fan types and were only in parts affected by kaolinization, whereas plagioclase has been decomposed to completeness. Autochthonous light minerals quartz, chalcedony (carnelian), and calcite are exclusive to the RKF, where silcretes and calcretes evolved in those stratigraphic units which in the OKF only brought about Ca, Fe and Ti anomalies. The OKF have a significant edge over the RKF in terms of kaolin quality and kaolin exploitation (providing less mechanical wear on LHD [load–haul–dump machinery] machinery). Allochthonous phyllosilicates have a more widespread occurrence in the RKF with muscovite, biotite and chlorite most common in the lowermost kaolin beds. By quality there is not much difference among the autochthonous phyllosilicates of the OKF and RKF. Kaolinite-group minerals, illite, smectite, and an illite–smectite mixed-layer are present in both types, but kaolinite-group minerals prevail in the OKF, with a downward-increasing trend of dickite. By contrast the amount of smectite and smectite–illite mixed layers increases at the expense of kaolinite upward in the stratigraphy. The evolution of the kaolin fan deposits can be subdivided into six stages. Each stage is representative of a peculiar process which translates into concentration, preservation and destruction of kaolin: stage 1 weathering and the formation of a kaolin regolith (constructive), stage 2 transport, deposition synsedimentary to early-diagenetic kaolinization (constructive + preserving), stage 3 synsedimentary to early-diagenetic smectitization of kaolin (faciesbound Pb mineralization only in the RKF) (preserving + destructive), stage 4 late-diagenetic kaolinization and formation of dickite (preserving + constructive) (not in RKF), stage 5 epigenetic unconformity-related Cu–Ag–Ni–As–Ba mineralization (vaguely expressed in the OKF) (preserving), and stage 6 unroofing, erosion and redeposition of kaolin (only in the OKF) (destructive). During the study a PIMA device has proven in this type of kaolin deposit to be an efficacious tool for capturing digital data in the field of exploitation and exploration of industrial minerals for the identification and quantification of clay minerals (quality control)

BACK MUSCLE FATIGUE MIGHT LEAD TO ALTERNATED SPINE LOADING IN RECREATIONAL ERGOMETER ROWING

The purpose of this study was to investigate fatigue related changes in spinal kinematics and muscle activity of back muscles during a 2000 m all-out performance on a rowing ergometer. Kinematic data of the trunk and EMG data of eight back muscles were recorded for ten subjects. A novel approach analyzing the spinal curvature was utilized identifying a significant increase (p \u3c 0.05) for the thoracic spine. For the M. trapezius a significantly decreased mean frequency (p \u3c 0.05) was found. The lumbar spine and the M. erector spinae showed no significant changes (p \u3e 0.05). These results contrast with findings for elite rowers which might be explained by a different rowing technique. Increased spinal curvature is a factor for injury risk. Thus, rowing programs should include monitoring of spinal curvature and strengthening of the stabilizing muscles

THE EFFECT OF RESTRICTING THE VISUAL SENSE ON THE KINEMATICS AND KINETICS OF A CUTTING MANOEUVRE

The purpose of this study is to investigate the kinematic and kinetic parameters when performing a cutting manoeuvre blindfolded. Male rugby and football players (n=7) performed a 60 degree cutting manoeuvre blindfolded and without restriction while recording kinetic and kinematic data. Restricting the vision led to a significant decrease of knee and hip flexion angle, a decreased inversion in the ankle and a tendency for higher knee-stiffness in the sagittal plane. The hip joint moment was significantly reduced while the knee joint moment was significantly increased. Considerable effects occurred in the kinematic and kinetic parameters, while the approach velocity and contact time showed trivial effects

CHANGE OF SPRINTING BIOMECHANICS IN THE ACCELERATION PHASE WHILE RESTRICTING THE VISUAL AND HEARING SENSE

Sprinting and short acceleration phases are common movements in rugby and football. The aim of this study was to evaluate if the running movement changed while senses were restricted. Nine rugby and football player performed in three conditions (no restriction, visual restriction and audivisual restriction) a 10m sprint. Kinematic and kinetic data were captured for step 4-6. The athletes ran significant faster than in the other two conditions although the contact time and stride cycle length did not significantly differ. A change could be seen in the extension moment of the hip and the ROM in the knee, both between no- and audivisual restriction. It was concluded that sensual restrictions effects the performance in a slowdown of the movement, but that during the 4-6 step only small changes seem to appear due to the visual restriction

Inverse Synthetic Aperture Radar Imaging of Space Targets Using Wideband Pseudo-Noise Signals with Low Peak-to-Average Power Ratio

With the number of new satellites increasing dramatically, comprehensive space surveillance is becoming increasingly important. Therefore, high-resolution inverse synthetic aperture radar (ISAR) imaging of satellites can provide an in-situ assessment of the satellites. This paper demonstrates that pseudo-noise signals can also be used for satellite imaging, in addition to classical linear frequency-modulated chirp signals. Pseudo-noise transmission signals offer the advantage of very low cross-correlation values. This, for instance, enables the possibility of a system with multiple channels transmitting instantaneously. Furthermore, it can significantly reduce signal interference with other systems operating in the same frequency spectrum, which is of particular interest for high-bandwidth, high-power systems such as satellite imaging radars. A new routine has been introduced to generate a wideband pseudo-noise signal with a peak-to-average power ratio (PAPR) similar to that of a chirp signal. This is essential for applications where the transmit signal power budget is sharply limited by the high-power amplifier. The paper presents both theoretical descriptions and analysis of the generated pseudo-noise signal as well as the results of an imaging measurement of a real space target using the introduced pseudo-noise signals

Fully polarimetric L-band brightness temperature signatures of azimuthal permittivity patterns - Measurements and model simulations

peer reviewedL-Band microwave radiometry over land mainly focuses on observations of horizontally (H) and vertically (V) polarized brightness temperatures. However, it has been demonstrated that measurements of the full Stokes vector [1] are sensitive to additional environmental properties, e.g. azimuthal plant row orientation. Furthermore, model simulations show that also a smooth surface with a periodic permittivity pattern can cause azimuthal dependencies of the Stokes parameters. The objective of this paper is to present fully polarimetric L-band measurement results from observations of a striped wood and styrodur target, when rotated 360° in small steps. Measurement results of a striped soil and open water target are also reported. Finally, measurements are compared to model simulations, with very good agreement within the validity range of the model (stripe thickness < ?/2)

Regional Travel Options 2007-08 Program Evaluation

To help implement the Growth Concept, Metro’s Regional Travel Options (RTO) Program works to increase awareness of non-SOV alternatives and increase the provision of those alternatives. The program complements other strategies, including land use policies and infrastructure investment. The most comprehensive data available for this evaluation come from commute surveys of employees at work sites that participate in outreach programs offered by TriMet. All of the RTO evaluations have used these data as a benchmark for overall progress, though the data only captures commute travel. The 2008 data reflect the commute patterns of about 120,000 employees commuting to 549 worksites. The long-term trend is positive, with the share of work trips made by modes other than single-occupant vehicles (SOVs) generally increasing since 1996 Figure 3. However, the data for 2007 and 2008 show a decline since 2006 in the share of work trips made on transit. Increases in bicycling and walking, compressed work weeks, and telecommuting helped offset that decline. The share of trips made in carpools and vanpools has remained about the same for the past four years, and is still lower than 1996

SUMIRAD - mechanisches Scannersystem Anforderungen an die BLDC-Motoren für Drehzylinder und Excenterantrieb

Das mechanische Scansystem des SUMIRAD Scanners besteht grundlegend aus einem schnell rotierenden Vollzylinder mit integrierter Metallplatte für den Azimuthscan und einem Excenter für die alternierende auf/ab Bewegung in Elevation. Die Komponenten sind in einem mehrteiligen Aluminiumrahmen eingebaut. Der Antrieb von Zylinder und Excenter soll über bürstenlose Gleichstrommotoren (BLDC Motoren) erfolgen. Die Anforderungen sind im Folgenden beschrieben