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561.
562.
Silcretes from Queensland (Australia) were dated by means of the electron spin resonance dating technique. The results range from 1.5 to 10.8 million years; therefore, these silcretes were formed between the upper Miocene and the early Pleistocene. For a conclusive interpretation of the data geochemical and thin section analyses were also carried out. ESR dating of silcretes for the first time offers a direct approach to a chronostratigraphic framework of the genesis of these duricrusts, and of the palaeoclimatic events attributed to them. 相似文献
563.
The Quaternary Herchenberg composite tephra cone (East Eifel, FR Germany) with an original bulk volume of 1.17·107 m3 (DRE of 8.2·106 m3) and dimensions of ca. 900·600·90 m (length·width·height) erupted in three main stages: (a) Initial eruptions along a NW-trending, 500-m-long fissure were dominantly Vulcanian in the northwest and Strombolian in the southeast. Removal of the unstable, underlying 20-m-thick Tertiary clays resulted in major collapse and repeated lateral caving of the crater. The northwestern Lower Cone 1 (LC1) was constructed by alternating Vulcanian and Strombolian eruptions. (b) Cone-building, mainly Strombolian eruptions resulted in two major scoria cones beginning initially in the northwest (Cone 1) and terminating in the southeast (Cones 2 and 3) following a period of simultaneous activity of cones 1 and 2. Lapilli deposits are subdivided by thin phreatomagmatic marker beds rich in Tertiary clays in the early stages and Devonian clasts in the later stages. Three dikes intruded radially into the flanks of cone 1. (c) The eruption and deposition of fine-grained uppermost layers (phreatomagmatic tuffs, accretionary lapilli, and Strombolian fallout lapilli) presumably from the northwestern center (cone 1) terminated the activity of Herchenberg volcano. The Herchenberg volcano is distinguished from most Strombolian scoria cones in the Eifel by (1) small volume of agglutinates in central craters, (2) scarcity of scoria bomb breccias, (3) well-bedded tephra deposits even in the proximal facies, (4) moderate fragmentation of tephra (small proportions of both ash and coarse lapilli/bomb-size fraction), (5) abundance of dense ellipsoidal juvenile lapilli, and (6) characteristic depositional cycles in the early eruptive stages beginning with laterally emplaced, fine-grained, xenolith-rich tephra and ending with fallout scoria lapilli. Herchenberg tephra is distinguished from maar deposits by (1) paucity of xenoliths, (2) higher depositional temperatures, (3) coarser grain size and thicker bedding, (4) absence of glassy quenched clasts except in the initial stages and late phreatomagmatic marker beds, and (5) predominance of Strombolian, cone-building activity. The characteristics of Herchenberg deposits are interpreted as due to a high proportion of magmatic volatiles (dominantly CO2) relative to low-viscosity magma during most of the eruptive activity. 相似文献
564.
565.
Hans Ulrich Roll 《Ocean Dynamics》1951,4(4-6):172-174
Ohne Zusammenfassung 相似文献
566.
Die Matrix der Fische VII. Essentielle Aminosäuren inAbramis undSalmo (Pisces) sowieTubifex (Vermes)
Ulrich A. Corti 《Aquatic Sciences - Research Across Boundaries》1950,12(1):94-98
Summary The amount of 10 and 11 amino acids respectively has been estimated in (a) a complete specimen ofAbramis brama; (b) muscles ofSalmo irideus; (c) Tubifex sp.
6. Mitteilung (im Druck) siehe C. r. XXIIe Congr. Chimie industr. (Barcelona) 1949. 5. Mitteilung (im Druck) siehe Verh. Schweiz. naturf. Ges. (Lausanne), 1949. 相似文献
6. Mitteilung (im Druck) siehe C. r. XXIIe Congr. Chimie industr. (Barcelona) 1949. 5. Mitteilung (im Druck) siehe Verh. Schweiz. naturf. Ges. (Lausanne), 1949. 相似文献
567.
Ulrich A. Corti 《Aquatic Sciences - Research Across Boundaries》1953,15(1):152-157
Summary The protein component of activated sludge is constituted by numerous aminoacids. The amino-acid content of 1 lb. of activated
sludge solids (produced by the purification of about 1000 gal. of sewage) may be quantitatively and qualitatively compared
with that of 0·50 gal. of fresh cow milk.
相似文献
568.
Hans Ulrich Roll 《Ocean Dynamics》1952,5(2-3):141-143
Summary This paper deals with the results obtained from temperature measurements within a range of 50 cm above and about 6 cm below the water surface. These observations were carried out on small pools in the tide lands around the island of Neuwerk in summer 1950 with the so called pan or knitting needle thermometer, a thermometer whose mercury bulb is replaced by a long and very thin-walled tube allowing the mercury to quickly adapt to fluctuations of temperature.
Mesures de la température effectuées près de la surface de l'eau
Résumè On expose les résultats des mesures de la température effectuées entre l'altitude de 50 cm au dessus de la surface d'une part et la profondeur de 6 cm environ au dessous de la surface d'autre part. Ces observations qui ont été faites dans des flaques de marée des bas fonds aux alentours de l'île de Neuwerk en été 1950 furent exécutées avec un thermomètre à aiguille à tricoter. L'originalité de cet instrument réside dans la forme de la cuvette de mercure, tube long à paroi mince qui assure une vite adaptation du mercure à la température du milieu environnant.相似文献
569.
570.
The seasonal occurrence of 94 benthic algal species, including Cyanophyta, was observed on a monthly basis over one year in the Patos Lagoon estuary (32°S, 52°W), Brazil, and showed three patterns of algal periodicity. An aseasonal group of 46 species was present throughout the year and two groups of 24 species each occurred either during summer and fall or winter and spring. The seasonal growth of 55 green, brown and red algae was correlated with monthly variations of salinity, water temperature, daylength and light radiation energy, which were measured daily in the estuary. Summer/fall peak growth was observed in 15 algae most of which correlated significantly with high salinities alone or in combination with other factors during this period. Growth peak of 11 species in winter/spring was principally a function of low water temperatures alone or together with a reduced light regime.Both periodicity of benthic algae and their seasonal growth, as a more sensitive measure of their floristic affinity, demonstrated the presence of cool temperate and tropical elements in this flora typical for warm temperate biogeographic regions. Correlations between seasonal variation of algal growth and selected environmental parameters aided in the evaluation of causal factors for algal seasonality. 相似文献