Comparison of metal homogeneity in grab,quartered, and crushed — sieved portions of stream sediments and metal content change resulting from crushing — sieving activity     

E. J. Mantei  R. L. Ernst  Y. Zhou 《Environmental Geology》1993,22(2):186-190

Restricted grain size sediment samples were collected along two streams. Metal content in some samples may have been influenced by landfill emissions. Each sample was divided into a grab portion, a quartered portion, and a portion crushed and sieved to a smaller size and then quartered. A duplicate sample from each of these portions was extracted. The Cu, Pb, Zn, Co, Ba, Fe, Mn, and Ca quantities were determined for each duplicate sample. Relative standard deviation was used to reflect homogeneity of metal content. Metal occurrence represented speciated metals or major components of chemical phases. Results indicated that variation of metal content among portions was uniform and did not vary as a function of absolute metal quantity. Homogeneity was similar in the same size grab and quartered samples. A more homogeneous metal state was displayed by the crushed and sieved sediments. However, this activity enriched softer chemical phases and associated speciated metals. It was concluded that sediments need not be quartered to obtain a better homogeneity of metal distribution and that field samples should not be crushed and sieved prior to chemical analyses. Assessment of sediments affected by metal emission sources must include a knowledge of metal homogeneity in individual samples.  相似文献   

Petrogenesis of some Ligurian peridotites—I. Mineral and bulk-rock chemistry     

W.G Ernst  G.B Piccardo 《Geochimica et cosmochimica acta》1979,43(2):219-237

Bulk-rock and mineral compositions of eleven lherzolitic specimens have been determined. Eight samples are from the Erro-Tobbio thrust sheet of the Gruppo di Voltri, western Liguria; three samples are from allochthonous eastern Ligurian masses within the External Ligurides. All specimens consist of spinel (±plagioclase) in addition to ol + opx + cpx, and have been derived from mantle portions of the South Alpine-Apennine lithospheric plate.Electron microprobe analyses of 11 olivines, 17 orthopyroxenes, 13 clinopyroxenes, eight spinels and one plagioclase have been performed. Except for Ca-rich and Ca-poor lamellae in some pyroxenes, and iron-enriched rims in a few spinels, the analyzed phases are remarkably homogeneous. Mineral compositions vary insignificantly from rock to rock. Consideration of major element partitioning in coexisting opx + cpx pairs, combined with the petrogenetic grid for aluminous lherzolite bulk compositions, yield the following provisional P-Tequilibration conditions: Erro-Tobbio complex, 1150 ± 50°C, 16 ± 6 kbar; External Ligurides, 1000 ± 50°C, 14 ± 6 kbar. Evidently the western Ligurian peridotites equilibrated at higher temperatures and possibly at slightly greater depths with the upper mantle than those from eastern Liguria.The lherzolite samples have nearly identical bulk-rock major element compositions. Comparisons with estimated compositions for the upper mantle, and for model pyrolite indicate that these Ligurian peridotites are primitive or only very slightly depleted in basaltic constituents. Thus, based on major element chemistry, the Ligurian peridotites cannot be regarded as residua left after extensive partial fusion, hence evidently cannot have produced large proportions of oceanic tholeiite liquid; on the other hand, they seem to represent a fertile mantle source for such melts.Relics of garnet have not been found, and apparent temperatures for both Erro-Tobbio and eastern Ligurian ultramafic suites exceed the classical intraplate oceanic geotherm; accordingly, these bodies may represent rising mantle material that recrystallized during ascent in the general vicinity of a spreading center, without having undergone extensive partial melting.  相似文献   

Statistische Untersuchungen über die tägliche Geburtenfrequenz in Wien     

Dr. Willibald Undt  Dipl.-Ing. Dr. Ernst Schuster 《Theoretical and Applied Climatology》1978,26(1):87-96

  相似文献   

The vertical structure of the atmospheric planetary boundary layer in undisturbed trade winds over the Atlantic Ocean     

Ernst Augstein  Heiner Schmidt  Feodor Ostapoff 《Boundary-Layer Meteorology》1974,6(1-2):129-150

During the Atlantic Expedition 1965 and the Atlantic Tradewind Experiment (ATEX) 1969, shipborne aerological measurements were obtained in order to investigate the thermodynamical and kinematic structure of the planetary boundary layer in low latitudes. Under suppressed convection, the subdivision of this layer into five sub-regions was found to be a rather permanent feature. Enhanced cumulus convection effects a smoothing of the thermodynamical discontinuities and leads sometimes to a destruction of the trade inversion. Due to the surface pressure distribution and the thermal wind distribution in the lower atmosphere, the actual wind speed and direction are nearly constant with height below cloud base. In the cloud layer up to the inversion, the wind speed generally decreases and the air flow tends to become more zonal.  相似文献   

Neue Bücher und Zeitschriften     

Teschke  H. Murawski  W. Zeil  Degens  Knetsch  H. -J. Schneider  G. Angenheister  E. Seibold  Th. Ernst  H. Bögel 《International Journal of Earth Sciences》1960,49(1):323-336

Ohne ZusammenfassungDie Transkription der Autorennamen und der geographischen Namen erfolgte nach den Richtlinien der Zentralstelle für wissenschaftliche Literatur, Berlin NW 7, vom 7. Dezember 1955.  相似文献   

Die Bedeutung der Kondensationskerne in der hygienischen Forschung     

Dr.med. Dr. Ernst Effenberger 《Pure and Applied Geophysics》1955,31(1):197-202

Zusammenfassung Eine erschöpfende Beurteilung des Verunreinigungsgrades der Luft ist nur auf Grund von Registrierungen der wichtigsten gasförmigen und korpuskulärne Beimengungen möglich. Eine grobe Aussage wird in vielen Fällen bereits auf Grund gleichzeitiger Messungen des Kern- und Staubgehalts der Luft gemacht werden können.Eine Aussage über die schädigende bzw. belästigende Wirkung einer Luftheimengung nur auf Grund einer Kernzahlbestimmung, wird nur in wenigen besonderen Fällen möglich sein. Als Beispiel sei angeführt, daß bei der Verunreinigung der Luft mit Tabakrauch die Kernzahl ein grobes Maß für den Nikotingehalt und die Kernzahl in Verbindung mit der Staubzahl ein Maß für den Gehalt der Luft an Tabakteeren darstellt.Auf Grund eigener Untersuchungen und den bisher in der Literatur veröffentlichten Meßergebnissen werden maximale Mittelwerte für den Kern- und Staubgehalt der Luft für verschiedene Orte angegeben. Somit wird es den Gesundheitsämtern möglich sein, durch einfache Kern- und Staubmessungen den geforderten Reinheitsgrad der Luft zu kontrollieren. Eine Vorraussetzung hierfür ist die Schaffung einheitlicher, leicht transportabler und einfach zu bedienender Meßgeräte.

---

Summary An exhaustive assessment of the degree of contamination of the air is possible only from records of its most important gaseous and corpuscular admixtures. A rough assessment will be possible in many cases by using simultaneous measurements of the nuclei and dust content of the air.A statement on the injurious or annoying effect of an air admixture based only on the determination of the number of nuclei will be possible only in few special cases. As an example may be mentioned that with the contamination of the air due to tobacco smoke the number of nuclei represents a rough measure of the nicotine content and the number of nuclei together with the number of dust particles is a measure of the content of the tobaceo tars in the air.Based on personal investigations and on the results of measurements so far published highest averages of the nucleus and dust content of the air for various places are given. Thus, it will be possible for the health authorities by means of simple measurements of nuclei and dust concentration to check the prescribed purity of the air. A condition for this is the design of uniform measuring instruments which are very portable and simple to operate.

  相似文献   

Zur Unterscheidung glazialer und Postglazialer Fliesserden     

Ernst Ackermann 《International Journal of Earth Sciences》1955,43(2):328-341

Zusammenfassung Abweichend von der vorherrschenden Auffassung einer ausschließlich periglazialen Entstehung der Fließerden in Mitteldeutschland wird festgestellt, daß im Holozän zwei verschiedenaltrige Fließerden aus Rötmergeln vorkommen. Da sich diese in der Substanz nicht von den glazialen Fließerden unterscheiden, ist es notwendig, zu ihrer Charakterisierung andere Kriterien, wie Struktur, Fließweite, Hanggefälle, Durchfeuchtung, Kleinmorphologie und Schichtfolge, heranzuziehen. Die Mergel des Röts neigen infolge ihrer Krümelstruktur bereits bei einer relativ mäßigen Durchfeuchtung zum Bodenfließen. Die Befunde werden hinsichtlich der klimatischen Bedeutung ausgewertet.  相似文献   

AOX‐Bildung bei der sonolytischen Oxidation von Salicylsäure in Gegenwart von Chlorid     

Svenja Lohner  Ernst Gilbert 《洁净——土壤、空气、水》2005,33(2):149-156

AOX‐formation by the Sonochemical Treatment of Salicylic Acid in Presence of Chloride Ultrasound shows great potential for improving water, wastewater and sludge treatment processes. However, a number of questions exist: for example the influence of suspended solids or salts. In this paper the influence of chloride in view of AOX‐formation should be investigated. As organic model compound salicylic acid (0.05…1 mmol/L) was used. Formation of AOX (adsorbable organically bound halogens) was measured in dependence upon chloride concentrations (1.4…141 mmol/L) and pH 2 and 9. Ultrasound irradiation was performed in glass reactor (500 mL) at 206 kHz and 353 kHz by continuous bubbling argon:oxgen (4:1) at a flow rate of 1 L/min into the solutions. The elimination of salicylic acid and the formation of hydrogen peroxide were not influenced by the presence of chloride (up to 56 mmol/L). The rate of salicylic acid elimination and the formation rate of hydrogen peroxide are at concentrations of mmol/(L min) levels but those of AOX formation of μmol/(L min) levels. The reactions leading to chlorinated by‐products can be seen as minor reaction paths. The yield of AOX depending on frequency, pH and chloride concentration lies between 10 μg/L and 900 μg/L. In acidic medium they were twice as high as in basic medium. Below the ratio chloride : salicylic acid of 2 mol/mol, AOX could not be identified.  相似文献   

Oxygen, magnesium and chromium isotopic ratios of presolar spinel grains     

Ernst Zinner  Larry R. Nittler  Roberto Gallino  Oscar Straniero 《Geochimica et cosmochimica acta》2005,69(16):4149-4165

  相似文献   

Seismogenic zone structure beneath the Nicoya Peninsula, Costa Rica, from three-dimensional local earthquake P- and S-wave tomography   总被引：3，自引：0，他引：3  

Heather R. DeShon  Susan Y. Schwartz  rew V. Newman  Victor González  Marino Protti  LeRoy M. Dorman  Timothy H. Dixon  Daniel E. Sampson  Ernst R. Flueh 《Geophysical Journal International》2006,164(1):109-124

  相似文献