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151.
152.
Yoshihiro Yokoyama Hiroshi Tsukamoto Tohru Suzuki Shohshi Mizuta Reiji Yoshinaka 《中国海洋大学学报(英文版)》2005,4(3):214-218
In this study, genes of two distinct tissue inhibitors of metalloproteinases-2 (TIMP-2) from Japanese puffer fish Fugu rubripes, Fugu TIMP-2a and TIMP-2b, were cloned. The open reading frames of Fugu TIMP-2a and TIMP-2b cDNAs are composed of 660 and 657 nucleotides and 220 and 219 amino acids, respectively. Both Fugu TIMP-2s contain 12 cysteine residues, which might form six disulfide bonds as in other animals' TIMP-2s. Reverse-transcribed polymerase chain reaction analysis showed the mRNAs of Fugu TIMP-2a and TIMP-2b to be expressed in some tissues examined with different expression patterns. These findings suggest that the two distinct Fugu TIMP-2s might perform different functions in Fugu tissues. 相似文献
153.
In July 2007, new marine heat flow data were collected at ten sites (HF01–10) in the central and southwestern sectors of the
Ulleung Basin (East Sea or Sea of Japan) as part of regional gas hydrate research. In addition, cores were collected at five
of these sites for laboratory analysis. The results show that the geothermal gradient ranged from 103–137 mK/m, and the in-situ
thermal conductivity from 0.82–0.95 W/m·K. Laboratory measurements of thermal conductivity were found to deviate by as much
as 40% from the in-situ measurements, despite the precautions taken to preserve the cores. Based on the in-situ conductivity,
the heat flow was found to increase with water depth toward the center of the basin, ranging from 84–130 mW/m2. Using a simple model, we estimated the heat flow from the depths of the BSR, and compared this with the observed heat flow.
In our study area, the two sets of values were quite consistent, the observed heat flows being slightly higher than the BSR-derived
ones. The evaluation of regional pre-1994 data revealed that the heat flow varied widely from 51–157 mW/m2 in and around the basin. Due to a large scatter in these older data, a clear relationship between heat flow and water depth
was not evident, in contrast to what would be expected for a rifted sedimentary basin. This raises the question as to whether
the pre-1994 data represent the true background heat flow from the underlying basin crust since the basin opening, and/or
whether they contain large measurement errors. In fact, evidence in support of the latter explanation exists. BSRs are generally
found in the deep parts of the basin, and vary by only ±15 m in depth below the seafloor. From the average BSR depth, we inferred
the background heat flow using a simple model, which in the case of the Ulleung Basin is approximately 120 and 80 mW/m2 for 2.5 and 1 km below sea level, respectively. 相似文献
154.
Hiroo Kagami Masaki Yuhara Shigeru Iizumi Yoshiaki Tainosho Masaaki Owada Yasuo Ikeda
Osamu Okano Shuji Ochi Yoshikazu Hayama and Terukazu Nureki 《Island Arc》2000,9(1):3-20
Osamu Okano Shuji Ochi Yoshikazu Hayama and Terukazu Nureki 《Island Arc》2000,9(1):3-20
Abstract The Ryoke Belt is one of the important terranes in the South‐west Japan Arc (SJA). It consists mainly of late Cretaceous granitoid rocks, meta‐sedimentary rocks (Jurassic accretionary complexes) and mafic rocks (gabbros, metadiabases; late Permian–early Jurassic). Initial ?Sr (+ 25– + 59) and ?Nd (? 2.1–?5.9) values of the metadiabases cannot be explained by crustal contamination but reflect the values of the source material. These values coincide with those of island arc basalt (IAB), active continental margin basalt (ACMB) and continental flood basalt (CFB). Spiderdiagrams and trace element chemistries of the metadiabases have CFB‐signature, rather than those of either IAB or ACMB. The Sr–Nd isotope data, trace element and rare earth element chemistries of the metadiabases indicate that they result from partial melting of continental‐type lithospheric mantle. Mafic granulite xenoliths in middle Miocene volcanic rocks distributed throughout the Ryoke Belt were probably derived from relatively deep crust. Their geochemical and Sr–Nd isotopic characteristics are similar to the metadiabases. This suggests that rocks, equivalent geochemically to the metadiabases, must be widely distributed at relatively deep crustal levels beneath a part of the Ryoke Belt. The geochemical and isotopic features of the metadiabases and mafic granulites from the Ryoke Belt are quite different from those of mafic rocks from other terranes in the SJA. These results imply that the Ryoke mafic rocks (metadiabase, mafic granulite) were not transported from other terranes by crustal movement but formed in situ. Sr–Nd isotopic features of late Cretaceous granitoid rocks occurring in the western part of the Japanese Islands are coincident with those of the Ryoke mafic rocks. Such an isotopic relation between these two rocks suggests that a continental‐type lithosphere is widely represented beneath the western part of the Japanese Islands. 相似文献
155.
Osamu Chiba 《Boundary-Layer Meteorology》1984,29(4):313-319
Several experimental results indicate that S
w (the skewness of the vertical turbulent velocity) increases with height, and K
w (the kurtosis) decreases with height in the neutral surface layer. The measured behavior of S
w and K
w with height under neutral conditions is shown to be consistent with available models for the gradient-diffusion and the pressure-velocity correlation. In addition, an estimate of the mode of the probability density distribution turns out to be helpful in interpreting the height dependence of K
w. 相似文献
156.
157.
158.
The bonded radii of anions obtained in topological analyses of theoretical and experimental electron density distributions
differ from atomic, ionic and crystal radii in that oxide-, fluoride-, nitride- and sulfide-anion radii are not constant for
a given coordination number. They vary in a regular way with bond length and the electronegativity of the cation to which
they are bonded, exhibiting radii close to atomic radii when bonded to a highly electronegative cation and radii close to
ionic radii when bonded to a highly electropositive cation. The electron density distributions show that anions are not spherical
but exhibit several different radii in different bonded directions. The bonded radii of cations correlate with ionic and atomic
radii. But unlike ionic radii, the bonded radius of a cation shows a relatively small increase in value with an increase in
coordination number. In contrast to atomic and ionic radii, the bonded radius of an ion in a crystal or molecule can be used
as a reliable and well-defined estimate of its radius in the direction of its bonds.
Received April 16, 1996 / Revised, accepted August 6, 1996 相似文献
159.
Osamu Kaburaki 《Astrophysics and Space Science》1982,82(2):441-456
The inertial effect on the structure of the magnetosphere of a rotating star is investigated, in the corotation approximation for a surrounding quasi-neutral plasma. The equation of motion reduces to a usual static balance equation between the electromagnetic and the centrifugal forces, in the rotating frame. However the MHD condition, which can be regarded as a special form of the generalized Ohm's law, is modified by the inclusion of inertial effect, with a violation of the frozen-in condition in case of a general (i.e., not restricted to corotation) plasma motion. The inertial effect on the electromagnetic field is summarized in a partial scalar potential named the non-Backus potential, which is proportional to the centrifugal potential in the corotation approximation.An approximate solution of this corotation problem is given, in which another characteristic radiusr
M
appears besides the light radiusr
L
. This radius defines a distance beyond which the inertial effect becomes dominant over the electromagnetic one, and is useful in estimating the magnitude of the terminal velocity of a centrifugal wind. A few examples of the modification of dipole magnetic field due to the inertial effect are visualized. In an oblique-rotation case, it can be seen that such a warp of the neutral sheet (the surface ofB
r
=0) is reproduced as observed in the Jovian magnetosphere. 相似文献
160.
The horizontal and vertical distributions of manganese in sea water, interstitial water and sediments in the Hiro Bay, Seto Inland Sea, Japan, have been investigated. The outflow from a pulp mill is the primary source of manganese in this bay. The industrial waste water contained 0.19 mg l–1 of manganese, mostly in a dissolved form. This manganese diffused out both horizontally and vertically into the surrounding sea water. The content of manganese in the liquid and solid phases in the sediments, however, are inverse with that in the sea water; namely the lowest concentration of manganese in the sediments was observed at the station near the outfall and manganese concentration increased with the distance from the outfall. 相似文献