Magnetic fields in quiescent prominences     

Einar Tandberg-Hanssen 《Solar physics》1970,15(2):359-371

We discuss the longitudinal component of the magnetic field, B , based on data from about 135 quiescent prominences observed at Climax during the period 1968–1969. The measurements are obtained with the magnetograph which records the Zeeman effect on hydrogen, helium and metal lines. Use of the following lines, H; Hei, D₃, Hei, 4471 Å; Nai, Di and D₂, leads to the same value for the observed magnetic field component in these prominences. For more than half of the prominences their mean field, B , satisfy the inequalities 3 G B 8 G, and the overall mean value for all the prominences is 7.3 G. As a rule, the magnetic field enters the prominence on one side and exits on the other, but in traversing the prominence material, the field tends to run along the long axis of the prominence.The National Center for Atmospheric Research is sponsored by the National Science Foundation.  相似文献   

Quantifying volume transports during SKAGEX with the Norwegian Ecological Model system     

Morten D. Skogen  Einar Svendsen  Marek Ostrowski 《Continental Shelf Research》1997,17(15):1817-1837

A coupled 3-dimensional physical, chemical and biological model system, NORWECOM (the NORWegian ECOlogical Model system), is validated and used to identify and quantify the short-term variability of the different water masses being transported into and out of Skagerrak. The model system is a nesting between a coarse grid model set up for an extended North Sea, and a fine grid defined in the Skagerrak/Kattegat area.Originating from the extensive SKAGEX (SKAGerrak EXperiment) database, several interesting events have been identified and become the focus of the modeling. Through interactive use of the SKAGEX data set and NORWECOM, it is possible to gain a new insight into a very complex hydrodynamic system, an insight that is hard to achieve based on measurements only.  相似文献   

Genetic impact of gadoid culture on wild fish populations: predictions, lessons from salmonids, and possibilities for minimizing adverse effects   总被引：2，自引：3，他引：2  

Bekkevold  Dorte; Hansen  Michael M.; Nielsen  Einar E. 《ICES Journal of Marine Science》2006,63(2):198-208

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Post World War II orcharding creates present day DDT-problems in The Sørfjord (Western Norway) - A case study     

Anders Ruus  Norman W. Green  Carl Einar Amundsen  Jens Skei 《Marine pollution bulletin》2010,60(10):1856-1861

The Sørfjord has a long history of agriculture and industry, and environmental monitoring has been conducted for decades, comprising analyses of contaminants in mussel, fish and sediments. DDT was used as an insecticide in orchards surrounding the fjord between World War II and 1970. Since the early 1990s, elevated concentrations of DDT were found in mussels and fish. Unexpectedly, DDT-concentrations increased towards present day, despite the discontinuation of use. The highest concentrations in mussels (in 2006) corresponded to about two orders of magnitude higher than background. Analyses of sediment core sections also indicated increased input towards present day. Shifts in climatic parameters, as well as increased amounts of soil dissolved organic carbon following a decline in atmospheric sulphate deposition may have contributed to this phenomenon. We warrant the need for increased knowledge of the effects of alterations in variables acting regionally and globally on the disposition of contaminants in ecosystems.  相似文献   

Development of Atlantic cod (Gadus morhua) exposed to produced water during early life stages: Effects on embryos, larvae, and juvenile fish     

Sonnich Meier  H. Craig Morton  Gunnar Nyhammer  Bjrn Einar Grsvik  Valeri Makhotin  Audrey Geffen  Stepan Boitsov  Karen Anita Kvestad  Anneli Bohne-Kjersem  Anders Goksyr  Arild Folkvord  Jarle Klungsyr  Asbjrn Svardal 《Marine environmental research》2010,70(5):383-394

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Candidate biomarker discovery in plasma of juvenile cod (Gadus morhua) exposed to crude North Sea oil, alkyl phenols and polycyclic aromatic hydrocarbons (PAHs)     

Anneli Bohne-Kjersem  Arnfinn Skadsheim  Anders Goksyr  Bjrn Einar Grsvik 《Marine environmental research》2009,68(5):268-277

In this study we have investigated protein changes in plasma of juvenile Atlantic cod (Gadus morhua) induced by crude North Sea oil and North Sea oil spiked with alkyl phenols and polycyclic aromatic hydrocarbons, a surrogate produced water composition. Using a proteomic approach, we identified 137 differentially expressed proteins at different levels of crude oil exposure. Many of the induced protein changes occurred at low levels of exposure. The results obtained with protein expression profiles after exposure to oil and surrogate produced water indicate effects on fibrinolysis and the complement cascade, the immune system, fertility-linked proteins, bone resorption, fatty acid metabolism as well as increased oxidative stress, impaired cell mobility and increased levels of proteins associated with apoptosis. Although the number of individuals and samples in this study is limited within each treatment group, the protein changes observed in this study represent a first screening for potential biomarker candidates in cod plasma reflecting potential effects of crude oil and produced water exposure on fish.  相似文献   

Catch, survey and life-history data for shrimp (Pandalus borealis) off Jan Mayen     

Einar M. Nilssen  Michaela M. Aschan 《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(21-22):2023

The Jan Mayen area has an extreme environment with low temperatures and infrequent, but abrupt temperature changes. The shrimp population here is considered to be on its edge of distribution. The life-history parameters are in the same range as in other high-latitude shrimp populations and are characterized by slow growth, large size at maturation and extended longevity. Irregular and sporadic commercial exploitation limit fishing mortality and give the population life-history parameters not previously seen in other areas. The Jan Mayen shrimp are large compared to, e.g., the Barents Sea shrimp and can reach a maximum carapace length (L_max) of 37 mm and an age of 10–11 years. The large size at sex transformation (L₅₀, >24 mm) and analyses of length–frequency distributions indicate that the shrimp may be 6–7 years of age before changing sex. The change in L_max and L₅₀ observed during the study period is probably caused by increased natural mortality due to sudden temperature changes or due to increased predation, rather than increased growth rates. The life-history strategy of shrimp in the Jan Mayen area can be explained by factors such as depth, temperature and population density variations caused by fluctuation in recruitment and mortality.The shrimp fisheries in the Jan Mayen area began in the late 1970s and reached an annual landing of 2000 tonnes in 1985, and since then landings have oscillated around 500 tonnes depending on a combination of factors. The survey indices of stock biomass varied between 3000 and 6600 tonnes. For most years, the highest shrimp densities are at a depth of 200–299 m, while large shrimp (and therefore also female shrimp) are dominant at depths greater than 300 m.Fish community data were studied as the composition of the demersal fish community is an integrated response to environmental conditions and as predation affects the shrimp stock. Polar cod and capelin are the most abundant fish species in the study area. A high number of blue whiting was registered in 1979, but the number declined in 1980 and 1981 as temperature decreased. During the surveys in 1994 and 1995, no blue whiting was registered. A few individuals were found again in the 1999 samples. The number of Greenland halibut has declined from the beginning of the 1980s to the 1990s.  相似文献   

On the steady mass transport induced by wave motions in a viscous rotating fluid     

Einar Maeland 《地球物理与天体物理流体动力学》2013,107(3-4):229-248

Abstract

The steady second-order motion induced by a first-order wave motion in a homogeneous, viscous and rotating fluid is examined. If the wave motion produces a steady Ekman layer suction by non-linear interactions, this suction must induce a steady component of interior, relative vorticity parallel to the axis of rotation in order to conserve mass. A boundary value problem for the determination of the induced, steady interior mass transport velocity is presented. The mass transport induced by a Kelvin wave is examined as an illustration and possible application of the theory.  相似文献   

Protein content and amino acid composition of young Atlantic halibut (Hippoglossus hippoglossus L.) captured in the autumn in north Norway     

Andreasen  Thomas Venno; Gulliksen  Bjorn; Haug  Tore; Nilsen  Einar M.; Ringo  Einar 《ICES Journal of Marine Science》1993,50(1):93-100

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Seismic migration and velocity analysis     

Einar Maeland 《Geophysical Prospecting》1997,45(4):641-651

Migration using an erroneous velocity gives a curve along which the energy is smeared. Associated with this curve is the caustic enveloped by the normal rays. It is possible to compensate for an erroneous velocity by a simple modification of the imaging principle. Formulae are derived for the general case when the velocity changes laterally, and the position of the caustic suggests how to modify the imaging principle so as to obtain an estimate of the NMO velocity. A synthetic example is used to illustrate the results of the analysis.  相似文献