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91.
Since 1967, New Zealand fur seals (Arctocephalus forsteri) have been seen in winter on Three Kings Islands (34°10'S, 172°08'E) in increasing numbers, up to 80 in 1969. Approximately 130 were also seen on Motupia Island (34°37'S, 172°48'E) in 1969.  相似文献   
92.
Abstract

Benthos near a sewage outfall discharging 69 000 m3 d?1 of municipal sewage into Tauranga Harbour was studied to determine the nature and extent of the impact caused by a small organic input. Sediment samples were collected about the outfall and analysed for particle size, sorting, mud content, readily oxidisable carbon (ROC), total Kjeldahl nitrogen (TKN), total phosphorus (TP), “oil and grease” (OG), and macroinvertebrates. It is concluded that observed patterns of physical sediment characteristics are mainly natural. Levels of ROC, TKN, TP, and OG were all highest at or nearby the outfall. However, chemical changes in the sediment related to the discharge seemed to be limited to within less than 50 m distance of the outfall. The distributions of ROC, TKN, and TP in the sediments were closely related to natural changes in mud content. The outfall had little effect on the distribution of total numbers of taxa or individuals, or the composition of macro‐invertebrate assemblages. Rather, these were most closely related to the (probably natural) variability in sediment particle size and sorting. Analysis of the distributions of common species showed that several were responding to the discharge, but such responses were limited to within 10 m of the outfall. Trie absence of extensive impact on benthos from the outfall probably related to high water velocities (up to 0.5 m sr?1 on a mean tide) over the outfall diffuser, which would ensure that any drop in sediment oxygen levels is small.  相似文献   
93.
宁波沿海陆源排污口假单胞菌属(Pseudomonas)分布特点   总被引:2,自引:2,他引:0  
采用高通量454焦磷酸测序方法对宁波沿海2个重点排污口、8个一般排污口的20个站位水样进行分析, 得到2011年3月、5月、8月、10月份各排污口假单胞菌属的分布情况。结果表明, 宁波沿海陆源排污口中存在较多的假单胞菌属。在检出的假单胞菌属中, 维罗纳假单胞菌(Pseudomonas veronii)和莓实假单胞菌(Pseudomonas fragi)的含量相对较多, 分别占56.72%、13.904%; 排污口中假单胞菌属的数量存在季节性差异, 3月份、5月份假单胞菌的数量相对较多, 8月份和10月份较少, 推测与季节性温度变化有关; 假单胞菌属的含量与排污口的主要污染物有关, 氨氮含量较高的排污口假单胞菌属的含量更高。  相似文献   
94.
To inform the future practices to be employed for handling waste water and grey water at the Swedish Antarctic station, Wasa, in Dronning Maud Land, the Swedish Polar Research Secretariat took the initiative to survey the practices of the 28 nations with stations in Antarctica. A questionnaire was sent out to all members of the Antarctic Environment Officers Network during the autumn of 2005. Questions were asked about the handling of waste water and grey water, the type of sewage treatment, and installation and operational costs. The response to the questionnaire was very good (79%), and the results showed that 37% of the permanent stations and 69% of the summer stations lack any form of treatment facility. When waste water and grey water containing microorganisms are released, these microorganisms can remain viable in low-temperature Antarctic conditions for prolonged periods. Microorganisms may also have the potential to infect and cause disease, or become part of the gut flora of local bird and mammal populations, and fish and marine invertebrates. The results from 71 stations show that much can still be done by the 28 nations operating the 82 research stations in Antarctica. The technology exists for effective waste water treatment in the challenging Antarctic conditions. The use of efficient technology at all permanent Antarctic research stations would greatly reduce the human impact on the pristine Antarctic environment. In order to protect the Antarctic environment from infectious agents introduced by humans, consideration should also be given to preventing the release of untreated waste water and grey water from the smaller summer stations.  相似文献   
95.
The dynamics of a coupled concrete gravity dam-intake tower–reservoir water–foundation rock system is numerically studied considering two hollow slender towers submerged in reservoir of gravity dam. The system is investigated in the frequency-domain using frequency response functions of the dam and the towers, and in the time-domain using time-history seismic analysis under a real earthquake ground motion. The analyzes are separately conducted under horizontal and vertical ground motions. The coupled system is three-dimensionally modeled using finite elements by Eulerian–Lagrangian approach. It is shown that presence of the dam significantly influences the dynamic response of the towers under both horizontal and vertical excitations; however the dam is not affected by the towers. When the dam is present in the model, the water contained inside the towers has different effects if the foundation is rigid, but it alleviates the towers motion if the foundation is flexible. It is concluded that the effects of foundation interaction are of much importance in the response of tall slender towers when they are located near concrete gravity dams.  相似文献   
96.
椒南化工区排污口附近海域的底栖生物状况   总被引:1,自引:1,他引:0  
利用2002年6~7月椒南化工区排污口附近海域生态调查资料,对该海域底栖生物的种类组成、数量分布及其生态群落多样性等进行了分析和研究,结果表明:(1)该海域底栖生物种类贫乏,多毛类Polychaeta、海地瓜Acaudinamolpadioidea及纵肋织纹螺Nassariusvari-ciferus等耐污种类为优势种;(2)该海域底栖生物生物量较低,且局部海域出现了无底栖生物现象;(3)该海域底栖生物多样性指数低、丰富度低、优势度大,表明底栖生物的生态环境已受到严重污染。  相似文献   
97.
半硬半软岩层小净距隧道洞口段监测分析   总被引:4,自引:0,他引:4  
针对雷公浦小净距隧道后行左洞洞口段具有半硬岩层半软岩层的特点,在开挖过程中,按照新奥法对隧道地表沉降、拱顶下沉、水平收敛、中间岩柱的位移、锚杆轴力、围岩压力和钢拱架应力等项目进行监测。监测结果表明,采用预留核心土法可以较好地控制围岩变形和应力;后行洞的拱顶沉降大于先行洞,且软岩一侧的下沉量更大;中间岩柱较薄弱,开挖初期往先行洞方向移动;降雨对围岩变形和压力影响较大,施工中应引起重视。研究结论可为类似条件下工程的设计、施工和监测提供借鉴。  相似文献   
98.
模糊综合评价法在土壤环境质量评价中的应用实例   总被引:4,自引:0,他引:4       下载免费PDF全文
The soil environmental quality was evaluated by fuzzy comprehensive assessment method,which could decrease the gradual change and fuzz of soil environmental pollution.The soil environmental quality at five plots of sewage irrigation region in Fuxin was validated by fuzzy comprehensive assessment method.The results indicate that this assessment method is feasible.And the method can also detect the soil environmental grades scientifically.The effects of different pollution factors on soil environmental quality can be estimated,and the pollution grades can be divided and evaluated.The method can provide the base for soil environmental plan and pollution prevention and cure.  相似文献   
99.
位于四川省凉山州的锦屏二级水电站是雅砻江上水头最高、装机规模最大的水电站。作为整个工程的核心构成部分的尾部地下发电厂房位于雅砻江右岸“V”型河谷岸坡山体内,地下水渗流场相对复杂。为确保地下厂房开挖施工方便和洞室群稳定,基于“先阻后排、以排为主、高水自流、低水抽排、外不入内、安全可靠、留有余地”的新设计理念,提出了一个完整的锦屏二级水电站厂区防渗排水的水害防治方案。综合渗控条件下的厂区三维渗流场计算结果,并考虑了一定的安全储备,确定了厂区防渗排水系统的参数。洞室群开挖实践表明目前采用的设计方案是安全可靠的。  相似文献   
100.
用硫化物矿物处理电镀厂废水技术研究   总被引:6,自引:0,他引:6  
大多数环境工程材料是通过表面作用( 吸附或共沉淀) 来清除水中的有毒有害物质的,这就要求材料本身具有高表面活性。在搞清硫化物固/ 液界面行为机理的基础上,本文采用高表面活性的硫化物作为吸附剂,以重金属污染大户———电镀厂的酸性废水作为处理对象,研制了一种低成本、高效益、以废治废、简便易行的重金属污染物处理技术———硫化物矿物→鼓气搅动→CaO 调pH 值。废水经处理后,完全可以达到国家规定的排放标准。该技术的研制,对保护和净化环境具有重要的现实意义,同时具有广阔的应用前景。  相似文献   
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