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91.
X-ray fluorescent spectroscope-analysis and the method of ratio matching can determine mean directions of sand movement and
geochemical classifications of sand grains. The result can also evaluate the physical condition of seabeds in a study area
(erosion or accretion). This method is applied to a sedimentation problem in the fishing port of Tsurugiji in Japan and the
result is in agreement with the comparison of the change of sea bottom topography measured in different years. The seasonal
changes of sand movement on this coast and sedimentation in the port are also investigated.
Received: 8 October 1998 · Accepted: 15 February 1999 相似文献
92.
New evidence of microbe origin for ferromanganese nodules from the East Pacific deep sea floor 总被引:3,自引:0,他引:3
HU Wenxuan ZHOU Huaiyang GU Lianxing ZHANG Wenlan LU Xiancai FU Qi PAN Jianming ZHANG Haisheng 《中国科学D辑(英文版)》2000,43(2):187-192
Using a fluorescence microscope and EPMA, abundant microbe ”bodies“ and clear microbic fluorescent microstructure are determined
in the ferromanganese nodules recently collected from the East Pacific deep sea floor. The microbic fluorescent structure
shows a close relation to the formation of the ferromanganese nodules. According to their morphological features, the microbes
are classified into two types: one is named clumpy microbe, which takes a bar-shaped manganese mineral as a pillar and grows
like fasciculate coral, resulting in irregular cauliflorate nodules with rough surfaces; the other is called filamentous microbe,
which grows in very thin arcuate and/or concentric circular laminae composed of a microbe layer and a metal (manganese and
iron)-rich layer, leading to potato-shaped nodules with relatively smooth surfaces. It also can be seen that the two types
of microbes are intergrown together, resulting in nodules complicated in compositions and shapes. 相似文献
93.
A new kinetic spectrophotometric method is developed for the measurement of manganese (II) in water. The method is based on
the catalytic effect of manganese (II) with the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 using the Nitrilo triacetic acid (NTA) as an activation reagent. The optimum conditions obtained are 40 mgL−1 RAWL, 1×10−4molL−1 KIO4, 2×10−4 molL−1 Nitrilo triacetic acid (NTA), pH = 5.8, the reaction time of 3.00 min and the temperature of 20.0 °C. Under the optimum conditions,
the proposed method allows the measurement of manganese (II) in a range of 0–50.0 ng mL−1 and with a detection limit of down to 0.158 ng mL−1. The recovery efficiency in measuring the standard manganese (II) solution is in a range of 98.5%–102%, and the RSD is in
a range of 0.76%–1.25%. The new method has been successfully applied to the measurement of manganese (II) in both fresh water
and seawater samples with satisfying results. Moreover, few cations and anions interfere with the measurement of manganese
(II). Compared with other kinetic catalytic methods and instrumental methods, the proposed method shows fairly good selectivity
and sensitivity, low cost, cheapness, low detection limit and rapidity. It can be applied on boats easily. 相似文献
94.
A new kinetic spectrophotometric method is developed for the measurement of manganese (Ⅱ) in water. The method is based on the catalytic effect of manganese (Ⅱ) with the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 using the Nitrilo triacetic acid (NTA) as an activation reagent. The optimum conditions obtained are 40mgL-1 RAWL, 1×10-4molL-1 KIO4, 2×10-4molL-1 Nitrilo triacetic acid (NTA), pH = 5.8, the reaction time of 3.00 min and the temperature of 20.0 ℃. Under the optimum con-ditions, the proposed method allows the measurement of manganese (Ⅱ) in a range of 0-50.0ngmL-1 and with a detection limit of down to 0.158 ng mL-1. The recovery efficiency in measuring the standard manganese (Ⅱ) solution is in a range of 98.5%-102%, and the RSD is in a range of 0.76%-1.25%. The new method has been successfully applied to the measurement of manganese (Ⅱ) in both fresh water and seawater samples with satisfying results. Moreover, few cations and anions interfere with the measurement of man-ganese (Ⅱ). Compared with other kinetic catalytic methods and instrumental methods, the proposed method shows fairly good selec-tivity and sensitivity, low cost, cheapness, low detection limit and rapidity. It can be applied on boats easily. 相似文献
95.
96.
To improve the expression efficiency of exogenous genes in Chlamydomonas reinhardtii,a high efficient expression vector was constructed.Green fluorescent protein(GFP) was expressed in C.reinhardtii under the control of promoters:RBCS2 and HSP70A-RBCS2.Efficiency of transformation and expression were compared between two transgenic algae:RBCS2 mediated strain Tran-Ⅰ and HSP70A-RBCS2 mediated strain Tran-Ⅱ.Results show that HSP70A-RBCS2 could improve greatly the transformation efficiency by approximately eightfold of RBCS2,and the expression efficiency of GFP in Tran-Ⅱ was at least double of that in Tran-Ⅰ.In addition,a threefold increase of GFP in Tran-Ⅱwas induced by heat shock at 40°C.All of the results demonstrated that HSP70A-RBCS2 was more efficient than RBCS2 in expressing exogenous gene in C.reinhardtii. 相似文献
97.
Zn-粘土催化剂对染料废水的O3氧化降解性能的影响 总被引:16,自引:0,他引:16
对于生物难降解性有机染料废水,用矿物催化剂进行复合催化氧化获 得了比较理想 的实验处理效果。以粘土为载体加载金属锌氧化物制成的可重复使用的固体催化剂,对人工模拟的染料废水进行复合催化臭氧氧化实验,获得了满意的效果。该法进一步提高了臭氧的降解效果,降低了处理成本。 相似文献
98.
99.
内波的实验室模拟是目前物理海洋学和流体力学研究的热点之一。结合实验室内波的模拟实验,近代光学技术、数字图像获取和计算机数据处理技术及三者相结合的技术,介绍内波实验中流场图像化测量领域的研究进展。同时对传统的纹影仪(横式)、立式纹影仪、数字纹影仪和片光源染料粒子示踪技术进行综述。并比较了各自特点及其在内波研究中的优缺点。 相似文献
100.
Ian C. Willis Chris D. Fitzsimmons Kjetil Melvold Liss M. Andreassen Rianne H. Giesen 《水文研究》2012,26(25):3810-3829
Digital elevation models of the surface and bed of Midtdalsbreen, Norway are used to calculate subglacial hydraulic potential and infer drainage system structure for a series of subglacial water pressure assumptions ranging from atmospheric to ice overburden. A distributed degree‐day model is used to calculate the spatial distribution of melt on the glacier surface throughout a typical summer, which is accumulated along the various drainage system structures to calculate water fluxes beneath the glacier and exiting the portals for the different water pressure assumptions. In addition, 78 dye‐tracing tests were performed from 33 injection sites and numerous measurements of water discharge were made on the main proglacial streams over several summer melt seasons. Comparison of the calculated drainage system structures and water fluxes with dye tracing results and measured proglacial stream discharges suggests that the temporally and spatially averaged steady‐state water pressures beneath the glacier are ~70% of ice overburden. Analysis of the dye return curves, together with the calculated subglacial water fluxes shows that the main drainage network on the eastern half of the glacier consists of a hydraulically efficient system of broad, low channels (average width/height ratio ≈ 75). The smaller drainage network on the west consists of a hydraulically inefficient distributed system, dominated by channels that are exceptionally broad and very low (average width/height ratio ≈ 350). The even smaller central drainage network also consists of a hydraulically inefficient distributed system, dominated by channels that are very broad and exceptionally low (average width/height ratio ≈ 450). The channels beneath the western and central glacier must be so broad and low that they can essentially be thought of as a linked cavity system. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献