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21.
22.
The p-hydroxyacetophenone ester of palmitic acid has been isolated from a sphagnum peat. Although fatty acids and phenolic compounds are common components of peat, naturally occurring phenolic esters of fatty acids are rare.  相似文献   
23.
Eight submersible dives between 3000 and 4200 m water depth were made off southern Japan in the eastern Nankai subduction zone. Benthic communities associated with chemosynthetic processes were discovered along the 800 m wide active tectonic zone, at the toe of the accretionary prism. A benthic community was also discovered along a zone of active compression, at the foot of Zenisu Ridge, 30 km south of Nankai Trough. Temperature measurements within the sediments below the benthic communities confirm that upward motion of interstitial water occurs there. Studies of water samples indicate advection of methane and light hydrocarbons. Specimens of the benthic community have been shown to have included in their shells carbonate resulting from methane consumption. Thus the benthic communities are related to overpressure-driven fluid advection along tectonic zones with active surface deformation. A 300 m high active scarp at the toe of the accretionary prism is related to relative motion in a 280° direction which is close to the 305° average direction of subduction in this area. The dives establish further that compressive deformation is presently occurring at the foot of Zenisu Ridge. The previous interpretation of the Zenisu Ridge as a zone of recent north-south intraplate shortening, 40 km south of the Nankai Trench, is confirmed. We conclude that tectonic evolution might well lead to future detachment of the Zenisu Ridge and overthrusting of this large piece of oceanic crust over the continental margin. Such a process might be an efficient one to emplace ophiolites over continents.  相似文献   
24.
Aircraft observations of oxides of nitrogen (NO y ), measured with a ferrous sulfate converter, over the sea surrounding the Japanese islands (30–43° N, 131–141° E) were carried out in the winter of 1983 and 1984 at altitudes mostly between 3 and 8 km. NO y defined here is the sum of NO, NO2, and other unstable oxides of nitrogen that are converted to NO by ferrous sulfate. The main observations were:
  1. Over the Pacific Ocean between the latitudes of 30–35° N, the observed NO y mixing ratio between 3 and 8 km was a fairly constant 200 pptv. The NO mixing ratio increased with altitude from 15 pptv at 3 km to 35 pptv at 7 km.
  2. Over the Sea of Japan, tropospheric NO y mesured between 1 and 6 km started increasing with latitude North of 35° N and reached about 1000 pptv at 40° N.
  3. NO y was measured in an air mass transported from the stratosphere near a tropopause fold region. When the ozone mixing ratio was between 80 and 140 ppbv, the NO y mixing ratio was about 200 pptv.
  相似文献   
25.
26.
A point explosion with thermal radiation in an axially symmetric inhomogeneous medium is investigated by generalizing the method of Laumbach and Probstein to include the effects of radiative cooling. As an example, a point explosion in the plane stratified transparent medium with exponential density distribution is calculated. It is shown that the focusing effect along the symmetry axis is enhanced by radiative cooling effect. Explosion models of extragalactic double radio sources are briefly discussed.  相似文献   
27.
Histological examination of gonads as well as chemical analysis of organotin compounds in tissues of the giant abalone, Haliotis madaka, was conducted to evaluate continuing endocrine disruption in abalone populations in Japan. Abalone specimens were collected from two different areas, Tsushima as a reference site and Jogashima as a site representative of declining abalone populations where serious organotin contamination had been observed, each month from January 1998 to March 1999. Scores were given to the development stages of reproductive cells in the ovary and testis. The degree of sexual maturation was evaluated by calculating the mean value of a histogram of these scores for the reproductive cells of each abalone. The temporal variations in degree of sexual maturation showed that female and male abalone from Tsushima matured synchronously, while those from Jogashima did not, which were similar to results of the previous study during September 1995–November 1996. Approximately 19% of the female abalone from Jogashima were masculinized with an ovo-testis, which was also similar to the result of the previous study. The masculinization of female abalone is reported to be induced by tributyltin (TBT) and triphenyltin (TPhT) from antifouling paints. Concentrations of the sum of butyltins (TBT, dibutyltin (DBT) and monobutyltin (MBT): ΣBTs) and the sum of phenyltins (TPhT, diphenyltin (DPhT) and monophenyltin (MPhT): ΣPhTs) in the muscle of abalone from Jogashima (n = 73) of 7.8 ± 9.0 ng/g wet wt. and 4.5 ± 6.8 ng/g wet wt., respectively, were significantly higher than those from Tsushima (n = 87) of 4.7 ± 4.9 ng/g wet wt. and 0.8 ± 1.7 ng/g wet wt., respectively (p < 0.05 for ΣBTs; p < 0.001 for ΣPhTs), although concentrations of TBT and TPhT in the muscle of abalone from Jogashima (n = 73) of 2.2 ± 2.5 ng/g wet wt. and 5.8 ± 5.1 ng/g wet wt., respectively, were insignificantly and significantly higher than those from Tsushima (n = 87) of 0.4 ± 0.6 ng/g wet wt. and 0.5 ± 0.9 ng/g wet wt., respectively, (p > 0.05 for TBT; p < 0.001 for TPhT). Thus, endocrine disruption as well as contamination by organotins in the giant abalone from Jogashima is still persisting.  相似文献   
28.
The comoving-frame equations of radiative transfer and moment equations to accurate terms of all orders inv/c are derived in the modified Lagrangian form. The equations exactly describe the interaction of radiation with matter in a relativistically moving medium in flat or curved spacetime. Two specialized sets of equations are presented: (1) the equation of radiative transfer and moment equations accurate to terms of second order (v 2/c 2), and (2) the transfer equation and moment equations for a radial flow in curved spacetime with the Schwarzschild-type metric.  相似文献   
29.
The kinetic approach ofWright andHobbie (1966) was used to determine the heterotrophic potential of Antarctic waters. Variations with depth and geographical location are discussed. Temperature studies indicate the psychrophilic nature of the microbial population. In samples having environmental temperatures of approximately –1C, significant activities were recorded at the lowest incubation temperatures tested (–3C). Activities increased with increasing incubation temperatures up to +3C but were somewhat depressed at +10C and above. By testing a wide range of substrates, qualitative differences were noted in the microbial populations of different areas.Highest rates of uptake were found in the euphotic zone whereas Vmax values of samples from depths of 500 m and below were in most cases unmeasurable.Published as Technical Paper No. 4259, Oregon Agricultural Experiment Station.  相似文献   
30.
The effects of the dispersant Corexit 9527 and Corexit with crude oil on the rate of glucose uptake and mineralisation were studied in Arctic and Subarctic marine waters and sediments. Essentially all of the 149 water and 95 sediment samples tested displayed decreased glucose uptake rates in the presence of either 15 or 50 ppm Corexit. Depressed uptake rates were observed at concentrations as low as 1 ppm. The mean concentration at which Corexit depressed glucose uptake by 50% was 12 ppm. The effect of Corexit was more pronounced on pelagic than on benthic microbial populations.  相似文献   
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