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1.
Lines of magnetic force, computed under the assumption that the solar corona is free of electric currents, have been compared with loop prominence systems associated with three flares in August, 1972. The computed fields closely match the observations of loops at a height of 40000 km at times 3–4 h after onset of the associated flares. Inferred magnetic field intensities in the loops range from 1300 G where the loops converge into a sunspot to 50–80 G at 40 000 km above the photosphere. The first-seen and lowest-lying loops are sheared with respect to the calculated fields. Higher loops conform more closely to the current-free fieldlines. A model of Barnes and Sturrock is used to relate the degree of shear to the excess magnetic energy available during the flare of August 7. On various lines of evidence, it is suggested that magnetic energy was available to accelerate particles not only during the impulsive phase of the flare, but also during the following 2–3 h. The particle acceleration region seems to be in the magnetic fields just above the visible loops. The bright outer edges of the flare ribbons are identified as particle impact regions. The dense knots of loop prominence material fall to the ribbons' inner edges.On leave from Tel Aviv University, Tel Aviv, Israel.  相似文献   
2.
Calcic skarn deposits related to Upper Cretaceous – Paleocene banatitic intrusions are widely developed in the Banat Mountains (southwestern Romanian Carpathians). There is a spatial distribution of banatitic igneous rocks and associated ore deposits in parallel zones, due to subduction beneath the southwest Carpathians. As a result three distinct petro-metallogenetic units developed, i.e. marginal unit: Moldova Nouă– Sasca; median unit: Ciclova – Oravita; and the inner unit: Dognecea – Ocna de Fier. The magmatism changed inland from monzonite and diorite → granodiorite occurrences to granodiorite → granite plutons. The related mineralization shifted simultaneously from Cu (Mo) to Cu-Mo (W) and eventually Fe(Cu)/Pb-Zn. The distribution of both magmatism and related ore deposits in parallel petro-metallogenetic zones is considered similar to that in the Andes. In particular, calcic skarns and related ore deposits that occur in these units show a transversal zonal variation represented by compositional features of pyroxene and granat, sequence of mineralization and metallogenetic environment. Such zonal characteristics represent an additional but nonetheless significant indicator for an Andean-type subduction-related setting. Received: 3 June 1996 / Accepted: 10 January 1997  相似文献   
3.
The anomalous X-ray pulsar 4U 0142+61 was recently detected in the mid infrared bands with the SPITZER Observatory (Wang, Chakrabarty and Kaplan: Nature 440, 772 (2006)). This observation is the first instance for a disk around an AXP. From a reanalysis of optical and infrared data, we show that the observations indicate that the disk is likely to be an active disk rather than a passive dust disk beyond the light cylinder, as proposed in the discovering paper. Furthermore, we show that the irradiated accretion disk model can also account for all the optical and infrared observations of the anomalous X-ray pulsars in the persistent state.  相似文献   
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Sorption behavior of Lanaset Red (LR) G on lentil straw (LS) was studied as a function of particle size, adsorbent dose, initial pH value, initial dye concentration, and contact time. Sorption kinetics data was well described by logistic model. Modified logistic equation can be used to explain effects of initial dye concentrations and contact time on the sorption of LR G with high R2 value. Freundlich model was found to be excellent in representing the equilibrium data. Thermodynamic parameters like free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were calculated by the use of Langmuir constant. Thermodynamic data showed that the sorption processes were spontaneous and endothermic in nature. Desorption process suggested that strong binding and weak interactions could be formed between adsorbent surface and dye molecules. Results revealed that LS has a remarkable potential for the sorption of LR G.  相似文献   
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Kefdag and Soridag chromite pods occur in upper mantle residual peridotites, which consist of harzburgite and dunites. The peridotites represent the residual of multistage, depleted upper-mantle peridotites. The chromitite bodies were formed during the uprising of chromium-rich picritic melts, through the residual upper mantle diapir, along the magma conduits. Chromitite grains were deposited in the caves of the magma conduits under the control of the convection currents.  相似文献   
8.
Genotoxic effects were evaluated in the somatic and gonadal cells of bivalve and gastropod molluscs inhabiting different sites of Klaip da port area in Lithuania. The occurrence of aneuploidy and polyploidy of cells, meiotic injures, centromere dissociation and fragmented polyploid nuclei as cytogenetic indicators of environmental stressors was assessed in snails Lymnaea ovata . The highest level of environmental genotoxicity (in 43.2 and 46.2% of studied cells) was observed in the tissues of snails inhabiting Malk Bay in 1995 and 1996. Dredging and thus removal of contaminated sediments from Malk Bay resulted in significant decrease (up to 27.2% in 1999) of cytogenetic injures in molluscs studied over the period from 1997 to 1999. However, the frequency of cytogenetic disturbances in molluscs from Vilhelmo Channel was increasing (1.8 times) from 1995 to 1999. Therefore, the ecological safety of the biggest drinking water supply for Klaip da population became questionable. Assessment of cytogenetic damage in Mytilus edulis (MN test) and the crustacean, Balanus improvisus, (aneugenic effects) inhabiting the Baltic Sea at B ting oil terminal has shown the highest genotoxicity level in the zone of sewage effluents from Palanga town and Ma eikiai oil refinery plant. Extensive cytogenetic injuries in gonadal cells indicated the potential long-term hazards of pollutants to ecological health and integrity of aquatic species.  相似文献   
9.
The Neolithic site of Çatalhöyük in Turkey contains thousands of mollusk shells, among them about 200 fossils. About 25 fossil gastropods and bivalvesoriginate in a Miocene fauna from the Mediterranean Tethys province, and are known from several localities in the Taurus Mountains, dating to the Miocene. The rest are scaphopods belonging to two species of Dentalium and dating to the Pliocene. The gastropods and bivalves were likely collected in the Karaman‐Mut Basin at adistance of about 50km from Çatalhöyük, while the scaphopods were brought from the Hatay Basin. Most of the fossil mollusks at the site were discovered in the upper phases, that is, late in the Pre‐Pottery Neolithic B sequence, and are associated with feasting activities. They may have been collected and brought to the site by the inhabitants as part of transhumance activities, or by visitors. © 2010Wiley Periodicals, Inc.  相似文献   
10.
An attempt was made to determine the absolute age of faulting by measuring fission track ages of epidotes from mineralization veins along fault and joint planes. The method was applied to epidotes from along faults and fissures in the Sinai Peninsula, which cut Precambrian rocks. Most samples yield Tertiary ages (32-11 m.y.) An Early Cretaceous event is also recorded (120-103 m.y.). Samples from country rocks (igneous and metamorphic) give ages older than 325 m.y. The results are compatible with previous geological information, and suggest that the method can be potentially useful for dating faults.  相似文献   
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