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241.
The Kärkejokk (jokk = Lappish for brook) is rich in sulfate and calcium, both elements having been considered enigmatic. To resolve these problems we collected waters at 13 sites during 27 June to 1 September 1996. Nine sites were in the Kärkevagge, and the others in the drainage towards lake Torne Träsk. Rain waters were collected the same period. Conductivity, pH, and temperature were measured in the field, whereas salt load and the elements Na, K, Ca, Mg, S, Si, Fe, Al, Mn, Zn, Sr, and Ba were determined in the laboratory.
Mixing models based on rain water and leaching products of the major bedrocks do not explain observed element patterns except in the lower parts of the jokk. However, oxidation of pyrite has formed acid, sulfate–rich solutions that released Ca and Mg from limestones, and Fe, Mn, Al, and Si, from black shales (Malmsten 1998; Malmsten et al. 2000). Conservative mixing models, using rain water, leached bedrock and pyrite, match the jokk waters quite well, and sulfur isotope data corroborate these findings. The nearby Låktajokk, and Vassijokk also contain much S.
Where these waters debouch they may deposit Si, Al, and Ca, but only little S on various rocks. Total rock analyses, thermodynamic and X–ray data suggest that gypsum, barite, or alunite are not formed in major quantities.
These models show that the hydrogeochemistry of the Kärkejokk may be less enigmatic than often assumed.  相似文献   
242.
Galgenbergite-(Ce) from the type locality, the railroad tunnel Galgenberg between Leoben and St. Michael, Styria, Austria, was investigated. There it occurs in small fissures of an albite-chlorite schist as very thin tabular crystals building rosette-shaped aggregates associated with siderite, ancylite-(Ce), pyrite and calcite. Electron microprobe analyses gave CaO 9.49, Ce2O3 28.95, La2O3 11.70, Nd2O3 11.86, Pr2O3 3.48, CO2 30.00, H2O 3.07, total 98.55 wt.%. CO2 and H2O calculated by stoichiometry. The empirical formula (based on Ca + REE ∑3.0) is $ \mathrm{C}{{\mathrm{a}}_{1.00 }}{{\left( {\mathrm{C}{{\mathrm{e}}_{1.04 }}\mathrm{L}{{\mathrm{a}}_{0.42 }}\mathrm{N}{{\mathrm{d}}_{0.42 }}\mathrm{P}{{\mathrm{r}}_{0.12 }}} \right)}_{2.00 }}{{\left( {\mathrm{C}{{\mathrm{O}}_3}} \right)}_4}\cdot {{\mathrm{H}}_2}\mathrm{O} $ , and the simplified formula is $ \mathrm{CaC}{{\mathrm{e}}_2}{{\left( {\mathrm{C}{{\mathrm{O}}_3}} \right)}_4}\cdot {{\mathrm{H}}_2}\mathrm{O} $ . According to X-ray single crystal diffraction galgenbergite-(Ce) is triclinic, space group $ P\overline{1},a=6.3916(5) $ , b?=?6.4005(4), c?=?12.3898(9) Å, α?=?100.884(4), β?=?96.525(4), γ?=?100.492(4)°, V?=?483.64(6) Å3, Z?=?2. The eight strongest lines in the powder X-ray diffraction pattern are [d calc in Å/(I)/hkl]: 5.052/(100)/011; 3.011/(70)/0-22; 3.006/(66)/004; 5.899/(59)/-101; 3.900/(51)/1-12; 3.125/(46)/-201; 2.526/(42)/022; 4.694/(38)/-102. The infrared absorption spectrum reveals H2O (OH-stretching mode at 3,489 cm?1, HOH bending mode at 1,607 cm?1) and indicates the presence of distinctly non-equivalent CO3-groups by double and quadruple peaks of their ν1, ν2, ν3 and ν4 modes. The crystal structure of galgenbergite-(Ce) was refined with X-ray single crystal data to R1?=?0.019 for 2,448 unique reflections (I?>?2σ(I)) and 193 parameters. The three cation sites of the structure Ca(1), Ce(2) and Ce(3) have a modest mixed site occupation by Ca and small amount of REE (Ce, La, Pr, Nd) and vice versa. The structure is based on double layers parallel to (001), which are composed of Ca(1)Ce(2)(CO3)2 single layers with an ordered chessboard like arrangement of Ca and Ce, and with a roof tile-like stacking of the CO3 groups. Perpendicular to (001) the double layers are connected to a triclinic framework structure with good cleavage parallel to (001) by a differently organized and more open part of the structure formed by Ce(3)(CO3)2(H2O). Based on the topology of the CaCe(CO3)2 single layer in galgenbergite-(Ce), structural relationships to rutherfordine, to aragonite and ancylite type minerals, and to lanthanite are outlined.  相似文献   
243.
Zusammenfassung Auf der Grundlage der Hansen-Schumacherschen Kippthermometertabellen werden vier Fluchtentafeln entworfen, deren Vorzüge in ihrer besonders schnellen Herstellungsweise, ihrer einfachen und zeitersparenden Anwendungsweise und ihrem verhältnismäßig geringen Raumbedarf bestehen.
Nomograms for correcting the readings of reversible thermometers
Summary Basing on correction tables for reversible thermometers after Hansen-Schumacher four nomograms are designed which are characterized by their particularly quick way of establishment, their simple and time-saving way of employment and the comparatively small space required.

Nomogrammes pour corriger les indications de thermomètres à renversement
Résumé Quatre nomogrammes sont présentés qui s'appuient sur les tables de correction pour les thermomètres à renversement d'après Hansen-Schumacher. Ces nomogrammes sont signalés par leur mode particulièrement rapide d'établissement et par leur simplicité et vitesse d'emploi; de plus, ils sont peu encombrants.
  相似文献   
244.
245.
The study presents composition data of 87 surface water samples from high alpine catchments of the Zermatt area (Swiss Alps). The investigated area covers 170 km2. It was found that the surface runoff acquires the dissolved solids mostly by reaction of precipitation water with the minerals of the bedrock. Total dissolved solids (TDS) vary from 6 to 268 mg L?1. All collected water shows a clear chemical signature of the bedrock mineralogy. The contribution of atmospheric input is restricted to small amounts of ammonium nitrate and sodium chloride. NH4 is a transient component and has not been detected in the runoff. Evaporation is not a significant mechanism for TDS increase in the Zermatt area. The chemical composition of the three main types of water can be related to the mineralogy of the dominant bedrock in the catchments. Specifically, Ca-HCO3 (CC) waters develop from metamorphic mafic rocks and from carbonate-bearing schists. Mg-HCO3 water originates from serpentinites and peridotites. Ca-SO4 (CS) waters derive from continental basement rocks such as pyrite-rich granite and gneiss containing oligoclase or andesine. The collected data suggest that, together with reaction time, modal sulfide primarily controls and limits TDS of the waters by providing sulfuric acid for calcite (CC waters) and silicate (CS waters) dissolution. If calcite is present in the bedrock, its dissolution neutralizes the acid produced by sulphide weathering and buffers pH to near neutral to weakly alkaline conditions. If calcite is absent, the process produces low-pH waters in gneiss and granite catchments. The type of bedrock and its mineral assemblage can be recognized in water leaving very small catchments of some km2 area. The large variety of water with a characteristic chemical signature is an impressive consequence of the richly diverse geology and the different rock inventory of the local catchments in the Zermatt area.  相似文献   
246.
Surging outlet glaciers are important in draining large ice caps, but the mechanisms controlling surge periodicities are poorly known. We investigated a sediment sequence from the glacier‐fed Lake Lögurinn in eastern Iceland, and our unique annually resolved data, based on sedimentary varves, imply that Eyjabakkajökull, an outlet glacier of Vatnajökull, began surging about 2200 cal a BP (before 1950 AD). Approximately 1700 cal a BP, the glacier started to surge at a uniform 34‐ to 38‐year periodicity that prevailed until the coldest part of the Little Ice Age when the periodicity almost halved to 21–23 years. Since the late 1800 s the surge periodicity of Eyjabakkajökull has returned to a longer period of 35–40 years. We suggest that surge periodicities of Eyjabakkajökull are forced by climatically driven mass balance changes, which may be a common forcing factor for similar surge‐type outlet glaciers. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
247.
Stress proteins (heat shock proteins, hsps) form part of the cellular protein repair system, and are induced by a wide variety of Stressors. To determine their suitability as tools for assessing sublethal sediment toxicity, we measured levels of members of the stress protein families hsp60 and hsp70 in benthic estuarine amphipods (Ampelisca abdita) exposed to sediments from 23 different sampling sites in San Francisco Bay for 10 d. Concentrations of sediment-associated xenobiotics were determined. Per cent survival was recorded and surviving animals were analysed for stress proteins using western blotting techniques. An inverse correlation (r2 = 0.44) was seen between amphipod survival and hsp64 levels, and hsp64 levels were positively correlated with concentrations of total polycyclic aromatic hydrocarbons (PAHs) (r2 = 0.5). Principal component analysis revealed that amphipod mortality was linked to a combination of several PAHs (phenanthrene, fluoranthene, pyrene, benzo(a)pyrene) and di-n-butylphthalate at southern San Francisco Bay sites. At northern San Francisco Bay sites, negative correlations were found between hsp64 levels and organotin compounds (MBT, DBT, TBT), and between hsp71 levels and the PAHs, benzo (b,k)fluoranthene and benzo(G,H,I)perylene, suggesting an inhibitory effect of these compounds on stress protein expression.  相似文献   
248.
Abstract. Species' depth distributions and abundances were visually assessed along 24 transects in a northern Adriatic assemblage of blennioid fishes (14 species of Blenniidae , 1 species of Triptery-giidue). Total abundance of blennioids was highest in 0.5-1 m depth, decreasing upwards and downwards. Species diversity (S hannon -W iener ) is highest at the shallowest depth (0-0.5 in). The curybathic species Parablennius incognitus, Lipophrys dalmatinus, Tripterygion tripteronotus , and Parablennius tentacularis were most abundant at all depths (relative to the species investigated). All stenobathic species were most abundant at 0-0.5 m. Depth distribution patterns and abundance ranks of species were similar at western, eastern, southern, and northern transects.  相似文献   
249.
Kurt  Kotrschal 《Marine Ecology》1988,9(3):253-269
Abstract. The utilization of empty holes of endolithic bivalves (Gttsirocluwnu dubui by Bknnius chdmcitinus , and Litliophaga lithophaga by all other species) as shelters by egg-guarding males of nine species of Adriatic Blenniidae is compared. A wide spectrum of entrance sizes to these "standardized" shelters is used with the most frequent utilization ranging between 1(H) and 275 mm: (11.2–18.8mm mean entrance diameters). As a trend within and between species, larger fish utilize holes with disproportionately wider entrances. There arc significant differences between species in the means of "fit" of the heads within the entrances: the heads of B. dulmaibuts, B. canaeve, B. adrialicus , and B. zvonimiri "fit" tightly into their entrances whereas the two large species, B.puvo and B. tentacularis , which only facultatively use holes of boring mussels for breeding, arc found in holes with "oversized" entrances. In most species mean shelter depth approximates mean body length. Species which tightly "fit" their entrances tend to stay longer when disturbed mechanically or chemically compared to those with only a loose "fit". The ecological and evolutionary significance of these patterns is discussed.  相似文献   
250.
Zusammenfassung Auf Grund eingehender Untersuchung der Südrandstörung des Wettersteingebirges wird der Nachweis erbracht, daß sie nicht einheitlich, sondern aus hunderten von Einzelverwerfungen in verschiedenen Richtungen zusammengesetzt ist. Diese Verwerfungen mit nahezu horizontalen Rutschstreifen stehen senkrecht, die seltenen Ausnahmen führen zu überschiebungen geringen Ausmaßes. Bezeichnend ist die plötzliche oder allmähliche Richtungsänderung der Verwerfungen und ihre Ablösung am Rande durch neue. Sie beweisen eine Summe von Differentialbewegungen gleichzeitig mit der Gesamtbewegung der Streifenschollen in O-W-Richtung. Das nötigt erneut zur Ablehnung einer, einheitlichen, S-N bewegten Decke.Auf die übereinstimmung mit den Ergebnissen vonCloos im Kristianiagebiete, wo ebenfalls seitliche Verschiebungen von Blöcken gegeneinander die einzige Erklärungsmöglichkeit bieten, wird hingewiesen.  相似文献   
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