全文获取类型
收费全文 | 413篇 |
免费 | 15篇 |
国内免费 | 6篇 |
专业分类
测绘学 | 2篇 |
大气科学 | 14篇 |
地球物理 | 92篇 |
地质学 | 131篇 |
海洋学 | 106篇 |
天文学 | 58篇 |
综合类 | 12篇 |
自然地理 | 19篇 |
出版年
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 14篇 |
2019年 | 7篇 |
2018年 | 8篇 |
2017年 | 17篇 |
2016年 | 7篇 |
2015年 | 7篇 |
2014年 | 15篇 |
2013年 | 18篇 |
2012年 | 13篇 |
2011年 | 15篇 |
2010年 | 10篇 |
2009年 | 20篇 |
2008年 | 31篇 |
2007年 | 15篇 |
2006年 | 23篇 |
2005年 | 24篇 |
2004年 | 10篇 |
2003年 | 14篇 |
2002年 | 12篇 |
2001年 | 5篇 |
2000年 | 14篇 |
1999年 | 11篇 |
1998年 | 7篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 5篇 |
1985年 | 8篇 |
1984年 | 7篇 |
1983年 | 10篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有434条查询结果,搜索用时 15 毫秒
181.
Journal of Oceanography - The water below a depth of 1,000 m in the Japan Sea was found to consist of two water masses, the upper layer (the Deep Water) and the lower layer (the Bottom Water). The... 相似文献
182.
Yuji Watanabe Atsushi Yamaguchi Hiroshi Ishida Takashi Harimoto Shinya Suzuki Yoshio Sekido Tsutomu Ikeda Yoshihisa Shirayama Masayuki Mac Takahashi Takashi Ohsumi Joji Ishizaka 《Journal of Oceanography》2006,62(2):185-196
The first CO2 exposure experiments on several species of pelagic copepods inhabiting surface and deep layers in the western North Pacific
were conducted. Living organisms were collected from two layers between the surface and 1,500 m between latitudes of 11 and
44°N, and they were exposed aboard ship to various pCO2 up to about 98,000 μatm. Mortality of copepods from both shallow and deep layers in subarctic to subtropical regions increased with increasing
pCO2 and exposure time. Deep-living copepods showed higher tolerance to pCO2 than shallow-living copepods. Furthermore, deep-living copepods from subarctic and transitional regions had higher tolerances
than the subtropical copepods. The higher tolerances of the deep-living copepods from subarctic and transitional regions may
be due to the adaptation to the natural pCO2 conditions in the subarctic ocean. 相似文献
183.
Atsushi Yamaguchi Yuji Watanabe Hiroshi Ishida Takashi Harimoto Kazushi Furusawa Shinya Suzuki Joji Ishizaka Tsutomu Ikeda Masayuki Mac Takahashi 《Journal of Oceanography》2004,60(4):773-787
As part of the research program WEST-COSMIC Phase I (1997–2001), vertical profiles down to the greater depths (0–2000 m or
5800 m) of the plankton community structure composed of heterotrophic bacteria, phytoplankton, protozooplankton and metazooplankton
were studied at one station in each subarctic (44°N) and in transitional region (39°N), and two stations in subtropical region
(30°N and 25°N); all in 137–155°E in the western North Pacific Ocean. The biomass of all four taxonomic groups decreased rapidly
with increasing depths at all stations, although the magnitude of depth-related decrease differed among the groups. As plankton
community structure, metazooplankton biomass and bacterial biomass occupied >50% of the total in 0–2000 and 2000–4000 or 5000
m strata, respectively, at subarctic and transitional stations, while bacterial biomass contributed to >50% of the total consistently
from 0 through 4800 or 5800 m at subtropical stations. Metazooplankton biomass integrated over the greater depths exhibited
a clear latitudinal pattern (high north and low south), but this was not the case for those of the other taxonomic groups.
As a component of metazooplankton, an appreciable contribution of diapausing copepods to the metazooplankton was noted at
subarctic and transitional stations, but they were few or nil at subtropical stations. As protozooplankton assemblages, heterotrophic
microflagellates (HMF) and dinoflagellates were two major components at subarctic and transitional stations, but were only
HMF predominated at subtropical stations. From biomass ratios between heterotrophic bacteria, HMF and dinoflagellates, “sinking
POC-DOC-heterotrophic bacteria-HMF-heterotrophic dinoflagellates” link was proposed as a microbial food chain operative in
the deep layer of the western North Pacific. All results are discussed in the light of latitudinal differences in the structure
and functioning of plankton community contributing to the ‘biological pump’ in the western North Pacific Ocean.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
184.
Akihiko Murakami Kazunobu Suzuki Akiko Yamane Tadao Kusama 《Journal of Oceanography》1985,41(5):337-344
Microbial degradation of five crude oils such as Arabian light, Berri, Murban, Khafji and Minas crude oil by a pure bacterial strain,Pseudomonas sp. isolated from the sea water sampled at Kawasaki Harbor in Tokyo Bay, was studied experimentally in the enriched seawater medium.The degradation of crude oils was determined in total residual oil and in four fractions of saturated, aromatics, asphaltene and column residue by use of the column chromatography with activated alumina.The saturated fraction was shown to be most biodegradable. The aromatics followed for all five crude oils examined and the asphaltene was biodegradable to some extent. The column residue was not apparently degraded byPseudomonas sp. within 30 days. Each of Arabian light, Berri or Murban crude oil was degraded from 59 to 63.5 %, Khafji crude oil 49 % and Minas crude oil, solid at room temperature, only 33 %. Degradation rate of the five crude oils was determined to be in a range from 2.88 to 17.3 mg-oil 1–1 hr–1 or from 6.0×10–12 to 1.56×10–10 mg-oil cell–1 hr–1. Relative degradation ofn-paraffins of different carbon numbers in the saturated fraction was found to be similar regardless of carbon number for the five crude oils. 相似文献
185.
186.
Seasonal and areal variation of continental aerosol in the surface air over the western North Pacific region 总被引:1,自引:0,他引:1
Shizuo Tsunogai Toshitaka Suzuki Takayoshi Kurata Mitsuo Uematsu 《Journal of Oceanography》1985,41(6):427-434
Weekly aerosol samples were collected for two years from 1981 at six stations in the western North Pacific region. The samples were analyzed for aluminum to determine the mineral dust concentration in the air. By combining our data with observations in the central and eastern North Pacific by a US research group, the following results and conclusions have been obtained. Spring peaks in atmospheric mineral dust were observed at all the stations accompanied byKosa episodes (hazes due to mineral dust of Chinese origin). The spring peaks, however, varied from year to year. The mean concentration of mineral dust depends not only on the distance from the Asian coast but also on the latitude of the sampling station. The half-decrease distance of the atmospheric mineral dust turned out to be 500–600 km for all latitudes in the western North Pacific. This indicates that the rate of deposition of mineral dust in the western North Pacific is much larger than that in the central and eastern North Pacific. 相似文献
187.
Simplified technique for the rapid determination of phytoplankton pigments by reverse-phase high-performance liquid chromatography 总被引:1,自引:0,他引:1
Reiko Suzuki Masayuki Takahashi Ken Furuya Takashi Ishimaru 《Journal of Oceanography》1993,49(5):571-580
A simplified technique for the rapid analysis of photosynthetic pigments in marine phytoplankton is described. The pigments extracted in N,N-dimethylformamide (DMF) are injected directly into the reverse-phase high-performance liquid chromatograph fitted with a photodiode array detector. We developed a new stepwise program; that is methanol-water (7525 v/v), methanol, methanol-acetone (8020) and methanol-acetone (6535). This program gives a good separation of at least 13 carotenoids, and 10 chlorophylls and their derivatives, completed within 20 min. The quantitative precision is high; the maximum standard error was less than 6%. The stability of pigments in DMF were also considered for application of this technique to the lab work on board the ship. 相似文献
188.
The temperature and salinity data obtained by the Iwate Fisheries Technology Center for the 25-year period from 1971 to 1995
were analyzed to clarify the seasonal variations in the sea off Sanriku, Japan. The variations of three typical waters found
in this region, the Tsugaru Current water, the Oyashio water, and the Kuroshio water are discussed in terms, of a T-S scatter
diagram referring to the water mass classification proposed by Hanawa and Mitsudera (1986). The mean temperature and salinity
fields averaged for each month show clear seasonal variation. Distributions of the Tsugaru Current water and the Oyashio water
can barely be distinguished in the fields deeper than 200 m since the Tsugaru Current has a shallow structure; however, the
fields at 100 m depth indicate remarkable seasonal variation in the area of the Tsugaru Current. At 100 m depth, the temperature
and salinity fronts between the Tsugaru Current water and the Oyashio water gradually disappear in January through April,
appear again in May, then become clearest in September.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
189.
Minoru Fujii Shinichiro Murashige Yuka Ohnishi Atushi Yuzawa Hitoshi Miyasaka Yoshimi Suzuki Hiroshi Komiyama 《Journal of Oceanography》2002,58(3):438-443
Decomposition experiments were conducted on cultured phytoplankton (Skeletonema costatum) in seawater containing decomposer and consumer of size less than 500 μm. We determined the decomposition rates of bulk particulate
organic matter (POM), the ratio of labile to semi-refractory fractions in the POM, and the POM carbon/ nitrogen (C/N) ratio
during decomposition. To identify the kinetic mechanisms involved in the reactions of different order (e.g., first- and second-order),
we studied the sensitivity of reaction rates to the initial concentration of POM, ranging from 2.4 to 71 mg-C L−1. The results showed that decomposition consists of two first-order reactions: decomposition of labile and of semi-refractory
particulate organic carbon (POC). The decomposition rate constants found for labile (0.13 day−1 at 20°C), and semi-refractory POC (0.008 day−1 at 20°C), and the carbon weight ratio of semi-refractory POC (13% at 20°C), were insensitive to the initial organic matter
concentration. The time-dependence of the C/N ratio was also independent of this initial concentration. The decomposition
rate constants and the content of semi-refractory POC did not change, regardless of the absence or presence of 25–500 μm organisms
in natural seawater.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
190.
Sanae Koizumi Tohru S. Suzuki Yoshio Sakka Kosuke Yabe Takehiko Hiraga 《Physics and Chemistry of Minerals》2016,43(10):689-706
This study develops a fabrication technique to obtain Fe-free and Fe-bearing (Fe:Mg = 1:9) olivine aggregates not only with high density and fine grain size but with crystallographic preferred orientation (CPO). A magnetic field (≤12 T) is applied to synthetic, fine-grained (~120 nm), olivine particles dispersed in solvent. The alignment of certain crystallographic axes of the particles with respect to a magnetic direction is anticipated due to magnetic anisotropy of olivine. The dispersed particles are gradually consolidated on a porous alumina mold covered with a solid–liquid separation filter during drainage of the solvent. The resultant aligned consolidated aggregate is then isostatically pressed and vacuum sintered. We find that (1) preparation of fully reacted olivine particles, with less propensity to coalesce; (2) preparation of a suspension with highly dispersed particles; and (3) application of a certain strength of the magnetic field are essential to obtain well-sintered and well-aligned aggregates. High density (i.e., <1 vol% porosity) and fine grain size (~1 μm) Fe-free and Fe-bearing olivine aggregates were successfully synthesized with uniaxially aligned a- and c-axes, respectively. Attempts to uniaxially align the magnetization hard axis and to triaxially align Fe-bearing olivine by rotating the suspension in the magnetic field succeeded in obtaining weakly developed CPO aggregates. 相似文献