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41.
42.
In this study, total metal (Al, Fe, Mn and Cu) and PAHs analyses have been done in the surface sediments. Sediment samples have been collected from seven parts of the Marmara Sea and the coast of Istanbul during 2009. Total Al, Fe, Mn and Cu contents vary between 1.8% and 5.4%; 1.1% and 2.8%; 122 and 259 μg g−1; 27 and 416 μg g−1, respectively. EF and CF values of Fe and Mn are lower than 1.5 and 1, respectively, in all the stations. Total PAH contents range between 135 and 6009 ng g−1 in the surface sediments. The origin of PAHs has been found pyrolitic according to the Phe/Ant ratio in the all stations. Contrastingly, at K0, MKC and MY1 Stations, PAH origins have been observed petrogenic according to the Flu/Pyr ratio.  相似文献   
43.
For experiments concerning the formation of oil–suspended particulate matter (SPM) aggregates (OSA), oil and sediment samples were collected from Campos Basin and six stations of Paraguaçu estuary, Todos os Santos Bay, Brazil, respectively. The sediments samples were analyzed for organic matter determined by the EMBRAPA method, nitrogen determined by the Kjeldahl method, and phosphorus determined by the method described by Aspila. The oil trapped in OSA was extracted following the method described by Moreira. The experiment showed a relationship between the amount of organic matter and OSA formation and consequently the dispersion of the studied oil. On the basis of the buoyancy of OSA and the ecotoxicological effects on pelagic and benthic community, the priority areas for application of remediation techniques are Cachoeira, Maragogipe, and Salinas da Margarida because of the large amount of oil that accumulated at the bottom of the experiment flask (5.85%, 27.95%, and 38,98%; 4.2%, 17.66%, and 32.64%; and 11.82%, 8.07%, and 10.91% respectively).  相似文献   
44.
提出了一个新的大气动力-热力学温湿参量——湿静力平衡温度(Ts)。它与密度温度(Tρ)有密切关系。作为Ts的应用示例,简化了积云一维时变模式垂直运动方程;提出了“载水气块”和“非载水气块”统一的新的“对流有效位能”表达式。结合实例,计算了“载水气块”和“非载水气块”两种情况下的对流有效位能(分别记作CAPEwCAPE)以及对流抑制能量(分别记作CINwCIN)等,“载水气块”与“非载水气块”两种情况的“对流有效位能”及“对流抑制能量”有较大差异。作为强对流天气分析预报的重要参数,目前计算对流有效位能和对流抑制能量的通用公式存在一定缺陷;在对“对流有效位能”的理解方面存在某些模糊认识和盲点。从新的观察角度对“对流有效位能”的概念做了详细分析并进一步阐明了其确切含义。新的方案同样可以方便地在T-lnp图上进行稳定度分析,并可根据新的公式对T-lnp的某些缺点进行修正。  相似文献   
45.
ɽ�������ִ��ؿǴ�ֱ�˶��о�   总被引:1,自引:0,他引:1  
?????????1980-2010?????????????????????α???????????????????????????????????????????????????????????????????о????????????30???????????仯??????????????????????????????????????????????????????б????????????????б???????????????б???????????α????????????????????????????????????????2.68 mm/a????????????????1.14~4.33 mm/a????????????  相似文献   
46.
Bodrum Peninsula is located between Hellenic Trench in the west and Gökova Fault Zone in the east which is affected by hundreds of earthquakes every year. Because of its active environment is allowed to monitor tracers/precursors continuously to analyse natural processes. This study focused on the determination of ground water radon (222Rn) concentrations in the Bodrum Peninsula in terms of seismic activities. Radon levels of ten ground water wells were measured periodically throughout the peninsula and these wells were divided into two groups according to the number of earthquakes they are exposed. Radon variations in second group stations are fairly significant as a result of high number of earthquakes. In these stations, radon continuously increased before the seismic storm and then decreased step by step. The results indicated that radon variations in ground waters of Bodrum Peninsula can be a good indicator for seismic storms instead of one specific event.  相似文献   
47.
���ϵ����ؿǴ�ֱ�˶������Ĺ�ϵ   总被引:1,自引:0,他引:1  
???????????1951??2011??????????????????????1951??1980??1980??1994??1994??2011??1951??2011??????α?????????????ε??α????????????????????????о??????α????????????????????7???????????????????????????????????????й??????????????????α????????????????????  相似文献   
48.
???????????????????????????????????????????α?????????????????????, ?о????????????????崹????????????????????????????α???????????????????????????????????????????????仯????ε?ò?????????????????????????????????????, ?????????????б??;????????????????????е???????????е???????е????????;????????????????1.00??2.00 mm/a??  相似文献   
49.
China's Yellow River has experienced its dramatically decreasing trend for the flow discharge since the construction and operation of large reservoirs located upstream. This low flow regulation has triggered a severe aggradation of the Ulan Buh Desert channel of the Yellow River because the declining flow exhibits no capability to scour and carry away large amount input of desert sands from the Ulan Buh Desert. Twenty monitoring cross-sections documented the Ulan Buh Desert channel has experienced its increasing aggradational trend in conjunction with its lateral migration decreasing trend from 1966 to 2005, which is opposite to the normal pattern of aggradation with deepening or symmetrical infilling for a channel located downstream of a reservoir. The channel aggradation can also be identified two stages: slow aggradation and rapid aggradation. Slow aggradation is characterized by the channel bed elevation rising 9.5 cm on average between 1968 and 1985, which responded to the operation of the Liujiaxia reservoir. During this period, the flow discharge was similar to pre-dam flow conditions but the sediment transport reduced to half of its pre-dam value. Because of about 0.24 × 108 t of desert sands entering the channel from the Ulan Buh Desert annually, this dilute flow indicated not to scour the channel as expected, but contrarily to cause the channel aggraded. Rapid aggradation followed completion of the Longyangxia reservoir with the channel bed elevation rising by 73 cm on average between 1986 and 2005. In this period, the combined regulation of Liujiaxia and Longyangxia reservoirs has caused the flow discharge decreasing dramatically, which is more beneficial for accumulation of the desert sands (0.19 × 108 t yr− 1 on average) in the desert channel, and led to the channel aggradation rate accelerated rapidly.  相似文献   
50.
沿海地区区域投资环境的综合评价   总被引:2,自引:1,他引:2  
中国沿海地区经济持续高速的发展,很大程度上得益于外国投资。吸引外资、刺激经济增长的关键在于不断地改善局部投资环境。文章的宗旨是对中国沿海主要经济发展地区的投资环境进行对比研究。运用层次分析方法,作者得到了一些有益的结论。  相似文献   
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