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111.
Tokumoto T Ishikawa K Furusawa T Ii S Hachisuka K Tokumoto M Tsai HJ Uchida S Maezawa A 《Marine environmental research》2008,66(3):372-377
Sonolysis and photolysis often exhibit synergistic effects in the degradation of organic molecules. An assay of fish oocyte maturation provides an appropriate experimental system to investigate the hormonal activities of chemical agents. Oocyte maturation in fish is triggered by maturation-inducing hormone (MIH), which acts on receptors on the oocyte surface. A synthetic estrogen, diethylstilbestrol (DES), possesses inducing activity of fish oocyte maturation, and a widely used biocide, pentachlorophenol (PCP), exhibits a potent inhibitory effect on fish oocyte maturation. In this study, the effects of the combined treatment by sonolysis with photolysis (sonophotocatalysis) to diminish the hormonal activity of DES and the maturation preventing activity of PCP was examined. By sonophotocatalysis, hormonal activity of DES was completely lost within 30min and the inhibiting activity of PCP was lost within 120min. These results demonstrated that sonophotocatalysis is effective for diminishing the endocrine-disrupting activity of chemical agents. 相似文献
112.
The mechanism governing the mean state and the seasonal variation of the transports through the straits of the Japan Sea is
studied using a newly presented, simple analytical model and a basin scale general circulation model (GCM). The GCM reproduces
the transports through the straits of the Japan Sea realistically owing to its fine horizontal resolution of about 20 km and
realistic topography. A series of experiments conducted by changing surface forcing shows that the annual mean wind-driven
circulation in the North Pacific Ocean is most responsible for the formation of the mean transports. It is also found that
the seasonal variation of the alongshore component of monsoonal wind stress over the North Pacific basin, especially that
over the Okhotsk Sea, is responsible for the seasonal variation of the transports. The simple analytical model can explain
these simulated features very well. The physical concept of this model is based on the formation of the around-island circulation
through the adjustment of coastally trapped waves and Rossby waves and geostrophic control at the narrow straits. It solves
the sea surface heights (SSHs) at the edge of each strait and the transport through it. The value of the line integral of
the SSH along the island is determined by the baroclinic Rossby waves approaching the island from the east and the alongshore
wind stress around the island. The basin scale seasonal variation of SSH along the coast induced by the variation of the alongshore
monsoonal wind stress can also be incorporated into this model by giving the SSH anomaly at the northeastern point of the
Soya Strait. Thus, it is suggested that both the mean state and the seasonal variation are caused mainly by wind stress forcing.
Minor modification by the seasonal heat flux forcing brings the amplitude and the phase of the seasonal variation closer to
the observed values. 相似文献
113.
Journal of Oceanology and Limnology - 相似文献
114.
115.
A unicellular cyanobacteriumSynechococcus sp. strain PCC 7002 was transformed with plasmid pQL1, on which β-lactamase gene (bla) and β-galactosidase gene (lacZ) were encoded. The transformant cells released β-lactamase into medium by an abrupt drop of osmotic pressure. This result indicates that this cyanobacterium recognizes and processes the signal sequence of β-lactamase, and accumulates the enzyme in periplasm. Repeated release of β-lactamase was possible by repeated osmotic shocks wihout, impairing cell viability. On the other hand, most of the β-galactosidase remained in cytoplasm under the osmotic shock.
相似文献116.
117.
A storage-efficient reconstruction framework for cartographic planar contours is developed. With a smaller number of control points, we aim to calculate the area and perimeter as well as to reconstruct a smooth curve. The input data forms an oriented contour, each control point of which consists of three values: the Cartesian coordinates (x, y) and tangent angle θ. Two types of interpolation methods are developed, one of which is based on an arc spline while the other one is on a cubic Hermite spline. The arc spline-based method reconstructs a G1 continuous curve, with which the exact area and perimeter can be calculated. The benefit of using the Hermite spline-based method is that it can achieve G2 continuity on most control points and can obtain the exact area, whereas the resulting perimeter is approximate. In a numerical experiment for analytically defined curves, more accurate computation of the area and perimeter was achieved with a smaller number of control points. In another experiment using a digital elevation model data, the reconstructed contours were smoother than those by a conventional method. 相似文献
118.
The change in groundwater chemistry along the groundwater flow path in the Matsumoto tunnel vicinity was studied, and the origin of the groundwater and dissoluted substances was determined. The relationship between the concentration of HCO3
–, Ca2+, and Na+, and CO2 gas pressure in the groundwater indicated that the HCO3
–, Ca2+, and Na+ were produced by the reaction of the CO2 gas in the groundwater and feldspar in the rocks. The relationship between the concentration of NO3
– and the Eh and pH values in the groundwater indicated that in an oxidative condition, ammonia-oxidizing and nitriteoxidizing bacteria used NH4
+ and produced NO3
– and H+, and in a reductive condition, denitrifying bacteria used NO3
– and produced N2 gas and OH–. The stable hydrogen and oxygen isotopic ratio in the groundwater and precipitation indicated that the groundwater originated from precipitation that had fallen on the area. The concentration of3H and the stable hydrogen and oxygen isotopic ratios in the groundwater suggested that it has been getting warmer climatically for more than 60 years. The stable carbon isotopic ratio indicated that the HCO3
– in the groundwater, excluding deep well water, originated from CO2 gas produced by organic matter in the soil. The deep well water, which had a higher concentration of HCO3
– than the other groundwater sampled, was thought to have acquired HCO3
– though contact with rocks. The36Cl/Cl ratio indicated the recharge age of the deep well water sampled at a depth of 760 m at the foot of the plateau was recent. 相似文献
119.
Ayako Shinozaki Hiroyuki Kagi Hisako Hirai Hiroaki Ohfuji Taku Okada Satoshi Nakano Takehiko Yagi 《Physics and Chemistry of Minerals》2016,43(4):277-285
Stability and phase relations of coexisting enstatite and H2 fluid were investigated in the pressure and temperature regions of 3.1–13.9 GPa and 1500–2000 K using laser-heated diamond-anvil cells. XRD measurements showed decomposition of enstatite upon heating to form forsterite, periclase, and coesite/stishovite. In the recovered samples, SiO2 grains were found at the margin of the heating hot spot, suggesting that the SiO2 component dissolved in the H2 fluid during heating, then precipitated when its solubility decreased with decreasing temperature. Raman and infrared spectra of the coexisting fluid phase revealed that SiH4 and H2O molecules formed through the reaction between dissolved SiO2 and H2. In contrast, forsterite and periclase crystals were found within the hot spot, which were assumed to have replaced the initial orthoenstatite crystals without dissolution. Preferential dissolution of SiO2 components of enstatite in H2 fluid, as well as that observed in the forsterite H2 system and the quartz H2 system, implies that H2-rich fluid enhances Mg/Si fractionation between the fluid and solid phases of mantle minerals. 相似文献
120.
Landslide hazard and risk assessment on the northern slope of Mt. Changbai, a well-known tourist attraction near the North Korean-Chinese border, are assessed. This study is divided into two parts, namely, landslide hazard zonation and risk assessment. The 1992 Anbalagan and Singh method of landslide hazard zonation (LHZ) was modified and used in this area. In this way, an Associative Analysis Method was used in representative areas to get a measure for controlling factors (slope gradient, relative relief, vegetation, geology, discontinuity development, weak layer thickness and ground water). For the membership degree of factor to slope failure, the middle range of limited values was used to calculate LHZ. Based on an estimation of the potential damage from slope failure, a reasonable risk assessment map was obtained using the relationship of potential damage and probable hazard to aid future planning and prediction and to avert loss of life. 相似文献