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91.
As the isotopic shift for the vibration rotation band is generally much larger than the isotopic shift for the corresponding electronic transitions and thus facilitating separation of isotopic lines, the vibration rotation bands of SiO may find use in the determination of isotopic abundance ratio Si28 Si29 Si30. To help identify the isotopic lines of SiO the wavenumbers for Si29O16 and Si30O16 have been calculated with an uncertainty of ±0.05 cm–1.Taking note of the fact that SiO shows strong vibration rotation bands in the spectra of some cool stars the equivalent width calculations for P(40) and R(40) lines of the 1-0 and 2-1 vibration rotation bands of Si29O16 and Si30O16 have been made at the centre of the disc for the model ZSM-74 using two values of isotopic abundance ratio and three values of dissociation energy.The search for the isotopic lines of SiO near 7 to 8m is recommended in low noise centre to limb sunspot spectrum scans with a view to help improve the isotopic ratio Si28 Si29 Si30 and oscillator strengths for the vibration-rotation transitions.  相似文献   
92.
A detailed study of classical polytropes in general relativity has been presented for O ((dP/dE)O) 1.0 and O((P/E O)O. The behaviour of various structural parameters with O/O, O and O are the values ofP/E and dP/dE at the centre) has been studied. The most important result of this study is the fact the qualitative behaviour of all the structural parameters depends only on the value of µO for the various assigned O values. The maximum value of surface red shift occurs when µO=0.6 and for O=1.0 it equals 0.618. These structures are gravitationally bound for µO0.8 and most so for µO=0.4. The maximum value of binding coefficient comes out to be 0.181 when O=1.0. These structures have been used to model neutron stars. The maximum mass of neutron star based upon such a model comes out to be 2.55M (for µO=0.4 and O=1.0) and maximum size comes out to be 15.0 km (for µO=0.2 and O=1.0). It is also seen that the structures are pulsationally stable for µ0.6.  相似文献   
93.
Attitude dynamics of a gravity oriented satellite in the presence of solar radiation pressure is examined. It is shown that even with a small offset between the satellite center of mass and center of pressure, significant pointing errors may result from the parametric excitation of the attitude motion by the radiation pressure. The phenomenon is illustrated through the analysis of a simple configuration involving a spherical shaped satellite possessing a nonspherical but axisymmetric mass distribution.  相似文献   
94.
The calculated equivalent widths of some lines of SiO in the umbral spectrum suggest that strong lines of Si28O16, Si29O16 and Si30O16 may be present in the sunspot ultraviolet spectrum. We also find that between 37 000 and 47 000 cm–1 the quasi-continuous absorption of SiO dominates all other absorptions.  相似文献   
95.
A consideration of the dissociation equilibrium of diatomic molecules in the Utrecht Reference Photosphere leads us to conclude that SH, SiO, CS, HF and HCl may show up in enough concentrations in the solar atmosphere. The number above photosphere for these molecules is comparable with or more than that of MgH.  相似文献   
96.
A wild and a cultured greenshell mussel (Perna canaliculus) population were compared for biochemical genetic variation at seven polymorphic and four monomorphic allozyme loci. Significant heterozygote deficiencies were observed for all polymorphic loci (La—1, La—2, Lap, Lgg—1, Lgg— 2, Pgi, and Pgm) for both populations (except the Pgi locus of the wild mussel population). Genotypic disequilibrium was calculated for both populations: genotypic frequencies were significantly non‐random at three pairs of loci among the wild mussels, and significantly non‐random at three different pairs of loci among the cultured mussels. All six pairs of loci which exhibited significant genotypic disequilibrium involved amino‐peptidases, suggesting that these loci form a linkage group, and that neither the Pgi nor the Pgm loci are associated with this group. Exact tests for population differentiation based upon population‐specific allele distributions indicated that four of the polymorphic loci were significantly heterogeneous among the two populations, whereas the remaining three polymorphic loci were not. Based upon the private allele system, the number of migrants (N m) between the populations was estimated to be 2.009, which, according to the private allele system, represents a high level of gene flow. These findings are discussed with regard to the population biology and genetic structure of this species.  相似文献   
97.
From 2011, lamprey (Geotria australis) populations in Southland, New Zealand have been affected by reddening along the length of the body and increased mortalities, termed lamprey reddening syndrome (LRS). Molecular testing, bacteriology, histopathology and epidemiology were used to determine if an infectious agent was present and to increase the understanding of this syndrome. An atypical Aeromonas salmonicida was detected from affected lamprey in 2011. This organism has not previously been reported from New Zealand. Investigative molecular testing indicated the organism was an uncharacterised, unculturable, atypical A. salmonicida and a likely incidental finding. Histopathology did not indicate an infectious process was involved, but suggested the reddening may be due to blunt trauma. Epidemiological investigation found the Mokoreta River had a significantly higher prevalence of LRS than others in the Southland region, but there was no clear reason why. To date, no infectious aetiology for this syndrome has been identified.  相似文献   
98.
A careful analysis of the sea surface temperature (SST) over the tropical Indian Ocean using the available SST data sets (namely, Hadley Center Ice SST, tropical rainfall measuring mission microwave imager SST, and optimum interpolation SST) at different time scales has been presented in the present study. By simple visual inspection of the SST plots, it has been shown that the qualitative prediction of Indian summer monsoon condition (weak/normal) and northern limit of monsoon (NLM) can be possible a month in advance using SST. The present qualitative study may be useful for common man to know the behavior of summer monsoon well a month in advance. Therefore, the qualitative study may enable the common man to show the application of satellite data to bring out the information regarding the onset of summer monsoon and related performance of Indian summer monsoon well in advance.  相似文献   
99.
Remote sensing techniques have been employed to identify and delineate soils in a part of Dibrugarh district of Assam. Landsat-4 MSS data in the form of FCC (4, 5, 7) were interpreted visually for physiographic analysis in conjunction with Survey of India topographic maps. Ground data were translated in terms of soils using composite interpretation map as base. The abstraction level attained was Families of Soil Taxonomy. Four major physiographic units were delineated, viz. active flood plain, recent alluvial plain, gently undulating old alluvial plain and gently sloping to undulating piedmont plain. Dominant soils identified are: coarse loamy Aeric Fluvaquents and fine loamy Typic Udifluvents in active flood plain; fine Typic Haplaquepts and fine loamy Aquic Dystrochrepts in recent alluvial plain; fine loamy Umbric Dystrochrepts and fine Ultic Hapludalfs in old alluvial plain; coarse loamy Typic Udorthents and fine Mollic Hapludalfs in piedmont plain.  相似文献   
100.
LOCAL SCOUR AROUND BRIDGE ABUTMENTS   总被引:2,自引:0,他引:2  
1 INTRODUCTION The protrusion of a bridge abutment or a spur dike into the main channel creates a disturbance and obstruction to the otherwise equilibrium state of sediment transportation in an alluvial river. The flow accelerates and separates at the upstream face of the abutment as it moves past the obstacle, creating a vortex trail that moves downstream in a direction approximately perpendicular to the structure. The result is that the bed around the structure is eroded locally. The l…  相似文献   
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